2006 Ford Mustang - Ruins Alternators & Batteries

Well, 3 have checked it out thus far and don't seem to find anything wrong. I believe the first two replacements may have been rebuilt. My understanding is the replacement in Feb. of this year was a new one - I could be wrong. Either way, it blows my mind that this will be the 5th alternator in a car under 10 years old.

Have they checked the ground,s from block, to frame,and to ecm all so,

2006 ford mustang. I bought a cheap OBDII Bluetooth reader from google for $10 an used the android app Torque to get the error codes.P0622 Generator Field "F" Control Circuit Malfunction and P1000. I replaced the battery and alternator still same error codes and check charging system. Just ordered a ECM from auto parts warehouse for $280. I think that is going to fix it.

I own a 2006 ford gt v8 mustang. 78,000 miles. Mines doing the same thing! Why? It only happened during really cold weather and is usually snowing. Check charging system error keeps popping up shortly after the car just dies. Replaced both battery and alternator. 1 month later ( today 12-25-14) same thing .... What's causing this and how the hell do I fix it???????

I have the same trouble, does anyone Know something about?

Bought new my 2006. She has 110k milres. I replaced the alternater first 3k. my girls light comes randomly too now some times pproceeded by a bit of a shutter. Gage reads OK and accessories don't drain charge. My also seems to be in wet/ colder weather. She also is kept out doors. Help!

The problem may be due to poor grounds between the negative battery post and the alternator. The floating ground will cause the field voltage to be too low at times which will then not charge the battery and at times will also cause the voltage output to high (18 to 20 volts) which will damage the battery. I installed a direct ground between the battery to the alternator bracket bolt to solve the issue in my Mustang.

im glad im not the only one this Is happening to iv had 5 alternators and at least 3 batteries in 3 years mine just went out again today, but I made sure my last alternator had life time warranty.. you need it with the 06 models I have heard everyone complain about them..

please check the voltage between the negative battery post and the alternator. if this is not close to zero you will be in the same position shortly. I fixed mine by adding a ground strap between the battery post and the alternator bracket. I am a retired Chrysler engineer. hope this helps.

just to be clear, If I install a wire between the negative battery post and the alternator bracket it will help to keep this from happening? Will this also fix a shudder that seems to happen if there is a couple accessories on at the same time (A/C, headlights)? What size wire should I use?

I pulled a ground cable off of a Dodge Ram in a salvage yard that was long enough. It already had the terminations at the ends for easy installation. A number 6 wire should do though. The alternator needs the field voltage to operate and the voltage regulator on the alternator uses the ground as the reference for the output voltage. The jumper keeps the ground to the alternator at the correct voltage. Poor grounds can lead to early failure of other things such as wheel bearings which are damaged by small arcing from the voltage differences between the drive train and the body. I cannot tell you the cause of the shudder without additional details. The engine controllers are usually designed to run at voltages as low as 8 volts and I think the engine would die shortly after the vehicle voltage dropped below that level.

OMG!!!!!!!! I so thought I was all alone! Mine overcharges and spikes up to 17.6 volts!! 08 v6 pony/premium packages. Mine started just 2 years after I got her brand new. Had the issue ever since. Up to replacing the alternator 6 times and about 7-8 batteries! Going within months now instead of years!

Well. I tried this. It did not stop my problem. It did however take it from battery needle going to high to only 3 quarters when it happens. Maybe bigger ground wire? I used a 6 Guage. Any suggestions? Anyone else have the same problem? Car will flicker headlights, map lights, tag light and it blows the blower motor resistor when it happens. Sometimes it have different symptoms. Alternator will overcharge up to 17.6 volts! And spikes randomly causing my ac to blow really hard and my subs to cut out along with blowing that resistor I mentioned before. Can anyone shine light on this? Mostly happens when coming to a stop or at a stop idling. Never happens while on the pedal. Give it gas when it happens and it stops doing it. I can't figure this out for the life of me. Check charging system light does not come on, no CEL either. Had ford test everything including the pcm and they say it's just fine. No codes. But obviously something is wrong. HELP!!!!! Or is this thread dead?

You may have very corroded ground wires on your car. Check the voltage at the battery while the car is running. Then while checking the voltage hook up a jumper cable from the negative post of the battery to the mounting bracket of the alternator. If the voltage changes then you need to still add a better ground.

Follow the ground wires between the battery to the body and the ground wires from the body to the engine. Clean all the terminations and make sure the bolts are tight.

I checked negative battery terminal to the alternator ground with a volt meter. Touching the negative and the case on the alternator I get a 0.034 at the highest. A little fluctuation but yeah. Positive side to positive lead on alternator I got .018-.020. Give the car some gas. Doesn't make a difference. Turn all electronics on. Doesn't make a difference. It charges normal, just spikes randomly up to 17.6 volts. Normal charge range is between 12.3 and 14.6 is what I see until it spikes. I will give my other grounds a good cleaning and what not today and see if that makes a difference. I'll also try the thing with the jumper cables. Any other suggestions? Was told my pcm could possibly be going out?

The Mustang that I was working on was a 2000 model. Yours might be different but I didn't think so. The alternator has a voltage regulator on the back side of it. The PCM doesn't have anything to do with the alternator unless the PCM has the voltage regulator built inside it. Later cars are sometimes built that way. The normal voltage should be higher than the 12.3 that you see. At 12.3 volts you are just measuring the battery voltage and the output of the alternator is probably zero which will lead to a discharged battery. Try the jumper cable when you measure the 12.3 volts and see if it doesn't jump to somewhere around 14 volts. Hope this helps. Steve

Thanks! I have no dying battery issues until it ends up killing a cell in the battery from being overcharged due to the spiking. But if it does I will then add a bigger ground wire. The one I'm on is an 8 guage. I'm going to try a 2. Also ford told me that my alternator does have a regulator. But that the regulator is PCM controlled. And that if the PCM is telling the regulator to charge so much then that's what it will charge. It won't charge until it's running because it's power is belt driven. But the pcm controls how much voltage the alternator puts out on my mustang. It's an 08 4.0.

look up how to do a full field test on your model. This will completely bypass the PCM and voltage regulator so that your alternator will run at full capacity during the test. This will help you eliminate the PCM or voltage regulator as the cause of the issue. Definitely do this before paying for a PCM!

if the pcm detects a low charge of the battery the voltage will go up to charge the battery after starting on a cold morning it is normal for the voltage to be high for awhile

it would take two number eight wires to be equivalent to one number six wire

I use to have this problem but i figured it out. I have a 2008 mustang GT premium that i bought brand new in '08. Not a problem until i reached 73,000 miles. I had this same problem and went through 4 alternators and 2 batteries.

But i figured out the problem and fixed it. It was the plug in the back of the alternator coming loose, losing connection, and going bad. I now have 133,000 miles and it just happened again.

I replaced the alternator and the plug and now 60,000 miles later, it happened again. That was almost 5 years ago. It was a good investment! So replace the plug and alternator and get back on the road. Lol.

I also have a 2006 Mustang GT 4.6L. When going to start the car, whether it sits for 2 hrs, 2 days or a week, it seems like the battery is low, I get the clicking like there is a loose connection and then it catches. It seems to happen more in the cool and cold weather that in the summer. I too have replaced the starter, alternator, and battery, to no avail. Ford has had it, a reputable auto mechanic I know has looked into it and nothing, Ford said it was fine, BS. I am now going to install the grounding strap between the battery and alternator and see what it does. Keeping my fingers crossed.

Did a Ford dealership work on any of your cars. This just happened to my son's car today and I just took it in. I replaced battery today and Ford says I need a new alternator. I am trying to preplan a problem. I am just a mom but on top of it. LOL

I hooked up a 4-gauge battery cable (to act as a ground) from the bottom alternator mounting bracket to the negative post on the battery and so far no problems. Keeping my fingers crossed though, just in case. Ford worked on mine and said nothing was wrong and that they didn't detect anything at all.

I have never had any of my Fords into a Ford dealership. The service folks would have a hard time finding this issue. It took me some time to find the root cause myself. I am a retired Chrysler engineer that designed and developed many electronic components for Chrysler and Dodge. The alternator needs an excitation voltage to start working. If the ground is not present at the time of the testing the alternator will not have an output and the test will incorrectly show that you need a new alternator. hope this helps.

My 2006 V6 Alternator went out on me a little over a month ago. First the radio turned off, then the windows stopped working, headlights turned off and finally the car died. This was after about 4 months of the "Check Charging System" light coming on about every hour then quickly vanishing. Worked fine for a month, but today - first cold day after a month of 90-105 degree weather - the Check Charging System light came on roughly 6 times in a 20 minute drive. Ill clean all the ground connections and replace the battery tomorrow, but does anyone have any more thoughts on what it may be?

T_Moore. You have the grounding issue that I have written about previously. You probably replaced a good alternator. You need to add the ground wire and not just clean up the grounds. This is really a design issue with the car that is easily corrected. You can quickly check this by using a jumper cable to attach the ground of the battery to the alternator mounting bracket and notice that the vehicle voltage returns to around 14 volts.

Steven_M It is already at 14 volts. Today after the drive, as soon as I pulled into the driveway without turning the car off I tested the battery. It was at around 14.5volts. I revved the engine and it fluctuated a little, but stayed between 14.1 and 14.7. Turning the car off it dropped down to 12.5. I'm already planning on replacing the battery because it is almost 3 months old, and i'll replace the ground wire as you said as well. Still, it seems like at least when i'm parked the voltages is within the range of what it should be.

The battery is 3 years old*

I think what happens is that the designed grounds become loose and corroded and during temperature changes and vibration you loose the ground to the alternator. Once the alternator looses the ground the alternator field voltage is lost and the alternator quits producing power. This will lead to a discharged battery. If you can charge the battery and it will start the car it does not need to be replaced. The 12.5 volts that you measured is a good sign that the battery is acceptable. You should be able to hook your volt meter to the output of the power plug in the car. Tape the voltmeter so that you can watch it easily as you drive. When you notice the voltage going outside of the proper operating range pull over and hook a single jumper cable from the negative of the battery to the alternator bracket and see if the voltage goes back to normal. Hope this helps.

I have the same problem.. My car's voltage keeps rising and frying batteries..could the after market (paperformance 200amp) fix my problem

Look up electrical problems water getting in due to a leak in firewall have any of you had water spilling in through the dashboard. I just read about this and I I have also replaced battery and alternator too many times, I'm not a mechanic but take a look I believe it's related to this issue we are all having

I have been reading even more stories about this water leak getting in to the electrical, mustangs going dead while driving. Leaks causing major corrosion etc. We need to force Ford to take responsibility for this issue rather than saling us alternator and batteries when it all starts with this sealant leak putting water in the electrical box and more. Please read these stories and let's demand ford fix the problem. I did not spend this kind of money on my mustang to find out about this problem through other ford owners when they could have at least informed us of it themselves before our issues escalted to more problems, rather than buying batteries and alternator etc. Trying to find out what's causing these issues repeatedly to happen

I bought my daughter an '06 Mustang GT in May as a college graduation present. 65K original miles Dealership installed a new battery 2015. Drove it home and the check engine light went on. Code indicated it was a.cam sensor. Brought it back to the dealer and they "fixed it" Drove home again (about 150 miles one way) and again the check engine light came on. Called the dealer and they authorized a local shop to make the repairs and shipped a new alternator (Internet search by the shop indicated the cam sensor code often is an indication of a defective alternator. They replaced the alternator in June and all was good until this afternoon when a dash warning light came on indicating to check the brake system and the car would not start. AAA responded and checked the alternator which showed it was charging at 9.45 V. They got the car started but the power windows seem to be running slow so appears to be a shortage of electrical power. Does this sound like a problem with the ground as well? Sounds like an easy fix if that is all there is to it.

The slow window motors are a sure sign of low voltage. Not likely that a short would develop in the window motor system without taking out the fuse. The electrical system needs to measure around 14 volts when the car is running. When the engine is off you should measure about 12.1 volts across the battery. If you do not see this measure the voltage from the ground terminal to the bracket of the alternator with the car running. This should be about zero. If it is not you need to add the additional ground strap that I have written about above. I see in the above posts problems concerning the corrosion development and water intrusion issues that cause the need for the added ground strap and I think that corrections should have been there all along as Ford would have known about this from their environmental testing. But as these vehicles are all out of warranty we just have to deal with the issues as best as we can as they arise.

My 2006 has a Saleen Supercharger, Ford Racing Cams, Ford Cam covers, Ford Racing Headers, 40,000 coils and 39 lb injectors. The car has only 26,000 miles on it and is used mostly in shows. I only run it about every 3 months, taking it to shows and keeping it covered most time in garage. Cams were installed May '15 and shortly afterwards it started dying on start up and then shurtered when driving. There was a voltage drop noticed by speed shop and belt tensioner replaced with Steeda heavy duty tensioner. I installed a PA Performance altenator, just to get the original out because of it's appearance. I ran the car on streets and highway for about 30 miles with no issues, untill crusing at 60 mph and the shuttering started again. The other day I started the car and within one minute it died. Now it won't start. No solution yet as I am going to have it hauled to the speed shop to see if they can figure it out. I have not installed the ground mentioned from the negative side of the battery to an alternator bolt, but when installing new altenator, every metal part was very clean and no corosion noticed. I will install the negative wire just to be on the safe side.

Steven M - I added a 4guage grounding wire from the negative post to the alternator and I still have the problem with power draining and starting issues. The alternator is new, so is the starter. The battery is an interstate and about 2yrs old and fully charged. where can the power drain be coming from? My mustang is an '06 with only 13,000 miles on it and garage kept. I even had it at shop and they would put it on a computer overnight to see where it was draining and they couldn't find it. Ford said they didn't notice anything either. Almost ready to sell the damn thing and get something different, but the wife really loves the car.

Since mine stays garaged mostly, I always have it on a trickle charger to keep the battery from draining. I know with all newer cars you always have some electrical items running, such as the clock, alarm (if equiped), and mostly anything else hooked up through the system. I'm not sure if the ignition switch kills everything is why I say "mostly anything".

We shouldn't have to keep trickle charge on it. I keep my Ford F150 outside, including in the winter here in Alaska and it is fine. This is the first of many vehicles I have owned that does this. I have had some $200 clunkers in my life that would start better than this car. Steve M pointed out the negative grounding system is weak, but even after adding a grounding strap to mine, it is still the same.

07 heritage, I don't know what could be the drain. Suggest getting a 1000 ohm resistor and putting it between the battery ground cable and the battery post. Measure the voltage across the resistor to determine the current drain. Then pull fuses out to see what may cause the largest part of the drain to go away. You should be able to find the short or defective part.

I have a 1996 ford mustang gt. Something is burning out my alternator as well. It's not spiking, it works when it wants to. It will be putting out 14 volts but then you shut it off get back in and it's putting out 11. I have exchanged 7 brand new alternators in the last 3 weeks. I took it to the shop and asked them to do a full diagnosis and they put in a new battery and laughed at me. Then I took it back less then two weeks later, told them its doing the same thing. They got back to me and said, oh, well the connectors were loose it running now. I get the car back and all the gauges aren't working and the alternator isn't kicking in. I bring it back, they said it's a blown fuse. I come back and they tell me, it's your alternator, gonna have to replace it again. So they did, again it was putting out 14 and then boom down to 11. All the cables seem to be fine and the grounds are all hooked up. Any ideas?

Tina, Sounds to me like a case of a floating ground. Please read my previous posts for details and solution. Steve

Thank you for the posts, i had the same problem. With charging system Error. I found a small break in the wire going to the alternator regulator. My part number was 1u2z 14s411 ta. 2006 mustang Gt. Its a 3 cavity pigtail for me. Finally i declare victory!!! $50 at the dealer. $10 on Ebay.

Update, after replacing the voltage regulator plug, 200 miles later guess what, Charging System light came back on. I replaced the remanufactured alternator with a new one from AutoZone. I'm sure that did the trick. I no longer have any spikes in voltage. The air conditioner does not Spike the lights do not flicker. Was the alternator all along. This was hard to track down because the alternator puts out the proper voltage of 14.1. What other forms said the diodes in the voltage regulator are junk. I took back the 5 week old Reman alternator to AutoZone and got a new one for only $11 more. If you don't see any more posts for me you know when it's fixed permanently lol. What a pain.

Sehunt, I think your problem will soon return. An alternator putting out 14.1 volts is not the issue. The spikes that you saw were probably due to a faulty ground between the negative side of the battery and the alternator bracket. I don't see how the diodes can be bad as you measured the 14.1 volts. The diodes don't go bad and then heal themselves.

I have been through the ringer with my 2006 Ford Mustang GT and the "Check Charging System" code. I have installed new alternators, new batteries, and have even replaced the alternator connector, which seemed to have done the trick. All was well for a couple months, until yesterday evening. As I was pulling into the garage from work, the "Check Charging System" code came back on unexpectedly. This morning, as I'm pulling into work, all of my electrical stuff cuts off inside of the car, but it was still running. When I parked it, I turned it off, and tried to turn it back on, and got nothing. Now, I'm here hoping that after reading this, installing aground wire will solve my issues. I'm extremely tired of this car and it's electrical issues, and the service department at Ford is of little to no help.

Okay guys please since we all have been through it. What is the first thing I should do other than replace the battery . Im Trying to fix it with out buying parts I do not need . I have bought a new battery & alternator is fairly new. Do I just buy the new alternator? & install that ground wire to the negative side??? 140k miles

Jcast36, First you figure out which parts, if any, are bad. Get a voltmeter, jump the car off to start it, measure the voltage at the battery. If you do not measure somewhere around 14.5 volts place one of the jumper cable wires between the negative post of the battery and the alternator bracket. If you now measure somewhere around 14.5 volts I do not think you need to change the alternator. If you can charge the battery and it holds its charge it is probably okay as well.

Steven M . I haven't yet tried the cable need to get a hold of a volt meter. As well my battery has drained the last 3 days as I type my battery is getting charged at parts store. Thanks for the response. Not sure how to go about issue on the battery draining...... bummer hoping to figure out soon

Steven M - I have added the 4ga cable from the battery to the alternator and my starting problem still exists. I have had the battery changed and tested, the alternator and starter are new. Could there be a ground in the plug on the back of the alternator?

Jcast36, Even a cheap Harbor Freight voltmeter will work. You need to know the voltages to figure out the issue. 07heritage, What is the voltage across the battery when the car is running? When the car doesn't start does it start slow like with a weak battery? When you jump the car off does it start quickly? Is the problem intermittent?

My power wire that runs from the back of the alternator to the positive terminal on the battery is fried and I need to replace it. Will an 8 Guage wire work? Going to buy that and crimp it to make a new one.

Yes im getting a volt meter today. What is happening my battery is going dead like no juice what so ever. I went & checked the battery thry told me it was no good. So I bought a new battery & was able to drive it 30 miles then my battery meter on dash started going down to where it was beyond low. I took the battery back in they told me that there was no juice left in the battery what so ever so had to leave it to charge again. My battery is being drained completely. 2 mechanics came & suggested to switch alternator.... Only thing that scares me it will happen after changing the alt.

Steven M. Plus when I jump it it will start but battery is low & car sound like it shouldn't drive so I just catch a ride .

kporterd, the positive cable has a "fuseable link" in it. If you look at the factory cable, not too far from the battery, there is a light blue section. This is the link. So, you need to make sure you have this or a fuse inline with the wire you're going to replace. American Muscle offers a new heavier gage cable with a fuse block installed. It's made by PA Performance, who also makes alternaters.

Jcast36. Let us know the voltages when the car is running across the battery posts. Check it with a charged battery. Also if the voltage is not around 14.5 volts attach a jumper cable from the negative battery post and the alternator bracket and measure the voltage across the battery cables again. Does the engine sound correct with a charged battery?

Steven_M, I have a similar issue that I'd like to get your opinion on. Went to start my 2006 V6 Mustang yesterday and had the gauges go kinda funny, the radio turn on, the CD player sounded like it was trying to switch CD's. When I turned the key further to start it, all I got was the loud clicking noise. Had to be somewhere so I took another vehicle. When I came back later and tried to start it again, the gauges and radio no longer worked at all and nothing happened when I turned the key. The battery was under 12v so I charged it to above 13v and tried again with no change in results. Headlights and dome lights still work and battery has held same charge for 24 hours, but power windows, locks, and gauges will not do anything. Thoughts?

I have had all the issues with my 2007 Convertible. I did legitimately lose an alternator due to it working so hard to recharge a constantly low battery, I replaced the alternator. My battery would still be dead if I let the car sit for 3 to 5 days. I replaced my factory stereo (I wanted Bluetooth anyhow) due to the Cd player chewing on imaginary Cd's, thinking that it was draining the battery, it was not, the problem continued. I do not drive my Mustang daily, sometimes it sits for 2 days sometimes for a week. After reading the TSB from Ford, I submitted and bought a $19 battery tender from Harbor freight. I plug it into the power outlet above my stereo each time I park the car. The tender keeps the battery topped off. I have had no issues since going the battery tender route, it has been about 9 months. Using the power outlet on the dash makes hooking up the tender a 20 second task, therefore I don't mind doing it. I put the tender on the ceiling above my car and the cable hangs down to the floor, I can reach out and grab it when I am parked, so I don't have to do anything when I get in or out. When leaving, I just unplug the cord from the dash and toss it out the window, it will be hanging there within reach when I return. I also have the water leak issue and do believe that the two problems are related. My car drips onto the passenger carpet from the SJB (Smart Junction Box) area. The SJB is a very common area for our cars to leak, once water gets in it is very hard to get it out. The moisture can move around causing different shorts at different times, making the problem very hard to trace. I keep mine garaged so I decided not to go after fixing the leak, from what I have read it can be a monumental task. I know that a battery tender is a Band-Aid and the problem is not fixed, but I pick my battles. For you folks that have to park outside, you may have to fix the leaks to ever solve this problem, until then these cars can eat alternators and batteries like pezz. Below is the Ford TSB on the battery drain problem: http://www.stangpit.com/wp-content/images/docs/s197-tsb/07-05-13.pdf Below is the TSB for the water leaks. I think they are related problems. http://www.acc.umu.se/~olsson/mustang/tsb07-14-06.pdf

In last 3 years I have put 5 alternators and 2 batteries on 07 v6. My wife went to 2 shops and dealer and they all said not charging at low rpm. I saw this post this morning and added additional ground from neg battery term to base of alt. Last night at low rpm meter showed around 12 volts and did not increase till around 3 thousand rpm. After additional ground it charges to 14 volts at idle. I used a battery cable that I had already. Thanks for posting this.

I have a 96 Thunderbird with (it sounds like) the same problem. While driving, the battery gauge suddenly drops substantially. It had done this before, about a year ago, but my husband fixed it....we thought. Like so many of you, he bought & installed both a new battery & alternator. This seemed to work until a couple days ago. Because I was soooo used to having to watch my battery gauge very closely so as to be as prepared as you can be when your car dies whilst driving, I just happened to notice the gauge acting very familiar by suddenly dropping for no apparent reason. Prior to my husband "fixing" it, I could keep it from dying whenever the needle dropped by revving the engine quickly either while in park, OR with my other foot on the brake. This would bring the gauge back up close to normal. This wasn't the case this time. When it started acting up AGAIN, he told me that there was something else causing it so replacing one or both again wouldn't actually fix it permanently. I should also add that my air conditioner / defroster had started acting weird a few months ago as well. While driving & using the a/c, it would suddenly STOP. I could still hear the compressor come on & feel a tiny bit of cool air through the vents although it wasn't being blown or forced out. The defroster did not force any air out either. Then, as fast as it stopped, the a/c would start working again. No rhyme or reason as to when or what made it start OR stop. I should also mention that water has been getting into the interior of my car from somewhere unknown for quite some time now. Other weird, electrical related things started happening recently add well such as my digital clock is not visible at all, my dash board, was either very dim, or one half not visible at all (at night). We both knew these things were probably related in some way. I know absolutely nothing about cars, how they work, etc. My husband is an electrician. After pondering what would cause this circumstance, and checking everything out with his electric meter thing, he came in to tell me that he was fairly sure the problem was a "floating ground". Not that I doubted him, (much) but I began searching the internet for similar stories, & more importantly, solutions for it when I discovered this thread. Upon reading these stories, and the solutions offered, I'm confident that it IS exactly the problem (floating ground) with my car. Basically he is going to do what Steven_M has been suggesting. He's working on it as I write this. Wish us luck!

Ok everyone tighten the hell out of the batteries I had mine tight I thought but no had to go tighter

I have an 07 Mustang V6 that recently got shipped back to me. I assume it had been sitting in the sun for about 2months straight. When I got it back and driving the "check charging system" indicator came on, A/C cut off along with all other electrical loads, battery spike to the High indicator. When I pulled over I noticed corrosion on the negative terminal as well as my less than 2 year old Optima battery bulging. At idle the battery indicator would sit in the normal position but as soon as I gave it gas, spiked to high. I drove it about 25miles to the nearest autoparts store. They replaced the battery, cleaned the negative terminal and I was able to drive it home about 300 miles away with no issue. As soon as I pulled up to my house, the battery spiked again. Took it to autozone for a battery/alternator test and it checked out fine. Thing is, I still had the same issues. Car runs fine, but I noticed whenever the A/C was on is usually when the issues would arise. Took it back to autozone and tested. They said the alternator was bad. Ford wants $350 for a new one, but recommended me to a place that rebuilds. I was told the diodes in the alternator were burnt out, possible issues with the voltage regulator and that was the reason why it was acting the way it was. Soon it should completely die. The last time my alternator went out was about 40k miles ago. I then got a rebuilt one and had no issues until now. I plan on taking it to get rebuilt tomorrow.

I have an 06 GT with a Shaker 500. I am not the original owner. I have the stock OEM battery that has died maybe 4 times in the last 2 years. I give it a jump and it usually lasts for a good while. However, I've been reading a lot about the Shaker 500 coming on and doing strange things when the car is off. I have read about a lot of folks who pull the fuses and the car responds beautifully. I've also read about the heat blanket that wraps around the battery ending up missing. For those who do not know, the heat shield keeps the heat in the engine bay away from the battery, as that can cause damage as well. Before you drop a lot of money into repairs, try these steps: 1 - Pull fuses for radio, give it a jump, wait and see. 2 - 26 bucks will get you a decent battery tender from Sears. 3 - New battery, grab the blanket too. May want to consider moving it to the trunk with a relocation kit if you live in warmer temperatures. 4 - Get Battery and Alternator tested at Auto Zone/Pep Boys/Whoever, and purchase accordingly. Buy NEW only. 5 - If you've replaced your Batt/Alternator within the last two years, then I'd suggest looking into your radio. Do a search on "Shaker 500 battery drain" and continue your search. 6 - Have a mechanic you trust check for improper grounding, wiring, DTC codes, FAULTS (different from codes) and if you opt to get work done, get warranties. Hope this helps.

ownastang, did they test the alternator on the car or on their tester? If they looked at it in the car and not the bench tester the alternator may be alright.

Steven_M, yes they used their battery/alternator tester both times.

So since my post 6 months ago, on my '06 GT, Saleen Supercharged, Saleen Shaker intake, Ford Racing cams, headers, 39 lb injectors and was 40K coils, TCP custom tune; I replaced the alternator with one of a better "show quility". I also at that time added a designated 6 gauge ground from the battery to the altenator. The tuner noticed the voltage drop on the original altenator prior to my replacing and added the ground. They also suggested adding a heavier positive, which I did. For me, it was discovered that the TCP tune was fighting the Saleen tune. Unlocking the code to change the Saleen tune was an issue because Saleen will not give the code to unlock the computer because of contractual agreements with Ford. I also noticed one of the plugs was burned more than others and that coil was brownish. So, I went back to the original 20K volt coils and new plugs. Fortunately, the tuner was able to locate a guy who used to work for Saleen and was able to unlock it and then install a custom tune using an HP tuner. Since this I have no issues and the car runs better than ever. This guy says with a modified setup that I should change plugs about every 25K miles. Bottomline; not sure what exactly solved the problem, but it seems to be okay now.

Steven_M, Took my alternator in today and pretty much had the whole thing rebuilt. Turns out the only thing that was working correctly was the rotor and pulley.The stator was bad, voltage regulator bad, diodes fried, rectifier bad. I think some of the issues were related to the bad battery. I've removed and replaced the alternator and so far everything seems to check out. Lets just hope nothing else is/goes wrong.

I've been having these same issues!! Replaced alternator a few weeks ago, and BAM she decides to struggle to crank when she does crank everything resets like the battery was dead no low voltage reading on the guages so today I take it to the shop that replaced my alternator they tell me its a bad battery so I go spend $130 on a new one! Its good right now, but I don't see this solving my problems for long!! HELP PLEASE!!! I have an 06 GT with very few small mods.

Please read all of my previous posts The voltages will read correctly when the resistances are low between the battery and the engine sometimes with vibration temperature and moisture the sources of the electrical breakdown occur I have thus far had to install the grounding strap which is described in my previous posts on 2 of my 3 mustangs

Steve, I have installed a 4 gauge strap from the negative side of the battery to the mounting of the alternator with no solution to the problem. Battery is full, but yet starting problems and draining persist. I am ready to sell this POS. It is an '06 with only 14,600 miles and has been garage kept. No mods and no accidents at all. Otherwise a great car.

Do you have about 13.6 volts all the time when the car is running? If not there is still something wrong with the charging system. If the charging system is okay get a 1000 ohm power resistor and put it between your negative battery terminal and the negative cable hook up the voltmeter across the resistor if you have a short draining the battery you will see a voltage here a small drain is normal but you can start pulling fuses and see what circuits are causing the issue by noting the amount of change in the voltage reading hope this helps

To the one with LEAKS ON PASSANGER SIDE ; Open the hood and look close to the front. There are a small black rubber pocket on each side. Pull it out and clean it .Once clean reinstert back in and just periodically check for trash. Mine was full of mud and old leaves that had blown in the car. My husband found the pocket and solved my problems for the leaks.

If you have a Shaker 500 stereo that is your problem. It draws power at times with cd errors when the car is off. Mine was also causing the "check charging system" once I replace the alternator. Just my 2 cents I took out the stereo car runs fine, no dead battery, cel, or check charging system. Replace it with something that actually works.

Its a common issue with this model and year of Ford Mustang. It is a grounding issue. As strange as it sounds go to Lowes or Home Depot and buy 3ft of 6 guage copper wire. Buy 2 one hole lug connectors like this one, (see picture). Also at Big Box Stores. Run the 6 guage wire from the battery ground to the alternator bracket. This will solve that issue. You will get many people who will tell you its not correct to do it this way, but my local Ford Dealership Recomended this to me. It stopped the issue. As well I zipp tied the ground to the wire harness to keep it neat.

My 07 GT had the battery draining problem. The alternator checked out ok and the battery checked out ok so I looked for something draining the battery when the car was shut off. I couldn't find anything. I solved the problem 3 years ago by putting in a 1000 CCA battery and a high performance alternator that puts out 200 amps.

My 06 GT died as well. Lost power to accessories one by one while sitting in traffic. Car had around 70,000 miles . I've owned it since 13,000. Had it towed home 25 miles. I replaced the alternator with a new one from ford. Yes I paid double what I could have from AutoZone but... It works perfectly. No changing voltages , no dimming or flickering lights. Just perfect . Now at 88000 miles still happy. 06 GT Vista Blue with White Stripes. Ford Racing CAI and Ford Racing Tune and Flow master axle backs.

The " check charging system" as also showed up on my 06 Mustang. 164,000 miles. I bought it new. Since my purchase have had 3 alternators and 2 batteries. Also, I have also had water leaking on passenger side when raining. Turns out that was from lots of spring tree droppings accumulating and clogged holes. (thank you Ford) Would this mess up with the fuse box on passager side? Taking a 1,000 mile trip soon, but now worried to drive it.

I have an 05 Mustang gt and was / am having the same problem as a lot of others on here. after going to the Ford dealership. they said I had a bad alternators so I ordered an after market alternators and installed it. afterwords I still had the same problem. I took the old one to Auto Zone to have it tested. there test said it was good. i reinstalled it and had Auto Zone test the new one. of-course it was good as well. I then went to reinstall the new one and it slipped in my hand just enough to see a black spot on the back side of the positive battery cable. when the pulley on the alternator is aligned the connector on the end of the battery cable to the alternator is so long it may touch the intake manifold causing it to rub and short out. mine only seem to short out when the engine warmed up. i bent it down a quart of an inch and 1 problem was fixed. now I will try the extra ground cable as stated in some of the post above.

Battery on my 2006 Mustang GT died. Autozone checked and alternator was bad. Changed the alternator myself. When I reconnected the car battery the cable from the alternator to my battery burned in half. Any suggestions?

@ cblakley I have an 06 4.0L Mustang and I recently replaced the alternator as well. If your connection to the alternator has blown out it may have been due to being overcharged. If I were you I'd try to rewire the alternator connection if your are confident in your electrical skills. You wouldn't want to keep a burnt cable on your alternator as that might just constantly drain your battery.

It is not the alternator or starter. We had trouble with my '07 4.6L v8 Mustang. It turned out to be a whole module under the dash. It was draining the system on a slow drain. After replacing it, no more dead batteries. I will get the part number and post it here. The part did cost about $500.

Helped my neighbor kid fix his 06 with this same issue. His was blowing the f40 fuse too so we troubleshot the engine wiring harness and found the wire to the coil rubbed raw on the engine block. Maybe check the wire harness for cuts. The back of the motor has a sharp edge that rubs on the harness sometimes.

The Mustang has a problem with water infiltration on the passengers side. This is a known, but unacknowledged design flaw by Ford. The water leaks down onto the fuse block in the passenger footwell. The components become wet and begin to deteriorate fast. This causes many problems such as the alternator overcharging, intermittent failures of control systems (climate, traction, radio, and charging). Even if you did not have a massive amount of water visible, the damage has been done and will continue until the block is replaced. You will also want to treat for mold as this is a serious health hazard and will continue to plague your pony. Found this out the hard and expensive way. :(

I have a 2006 Mustang II I took it to the dealership told me nothing was wrong but I needed a new thermostat control unit a new radio a new transmission they said probably the steering was going to go out and they didn't put anything back together after it got soaked from water from outside to the inside with like buckets now everything's going bad I think Ford knows about the whole problem

I want the dealer to pay how do we get a class action suit for them ignoring it!

I know this is old Post but I figured out this a few days ago with a customer's car and his is a 5.0 mustang the clutch on the altenator is failing the vehicle is designed to be up inside the RPMs and the clutch on the alternator is not designed for it so we updated his alternator to a boss alternator play that's been doing very very well little bit more expensive has a bigger clutch and a bigger pulley and it fit in the car just fine

Just got a 2007 V6 and the alternator looked new but was only putting out 12.7 V so I swapped it for a Reman Ultima 135 Amp Alternator from O'Reilly. After install alternator was putting out steady 13.7 V. Battery tested good. Alternator died (today) after three days while driving and barely got home on battery. Headlights have flickered since I got the car and that seems related. I don't think that the headlight switch is bad because new led driving lights also flicker same and they are wired to an accessory fuse with no switch. The flicker may be a little affected by RPMs but flicker is pretty steady at idle or speed. I have checked and tightened engine to chassis, chassi to battery grounds. I replaced the three wire pigtail on the alternator and put in another warrantied Ultima 135 Amp Alternator from O'Reilly. For all I know they all come with bad diodes, but who knows. Added a 4g ground from alternator to battery just to be safe this time. Detected a very small voltage there before grounding. Checked resistance between all points (alternator, block, battery) and no resistance found. Engine to chassis ground is tight and good. Headlights still flicker. I am thinking next step is plugs and plug wires, but I am going to wait a week to see if the new alternator gets killed first. I have read this and all the other threads out there on Mustang flickering headlights and alternator problems and there are a lot of guesses and lectures about Chinese parts etc. and that is not much help. Also the "Well I have no idea but try . . ." sort of responses are no help. I am already in spend mode getting nowhere fast trying to troubleshoot logically.  What I really want to know is (1) whether anyone has actual knowledge of anyone ever actually solving the flickering headlight issue? or (2) solving the car killing the alternators issue? From what I have read over the past three days, not one person has nailed this at a dealership or otherwise despite the problem being very common with these cars. God, I hate electrical problems.

I have been reading all this information about alternators, wiring, lights, endlessly. There is a common issue. The ground function is either missing in some cases or intermittent in other cases. No one is going to put their finger on a absolute one part repair because that is not possible. It is important to have reliable information going back and forth, with known repair results. A one month repair is not good enough to pass on as a legitimate fix. If a person does not know anything about reading meters, and know exactly what a reading, being voltage, amperage, or resistance means, dont guess or claim a fix if you truly do not know what fixed the issue. A fix for a condition is getting the condition to happen, by doing something to bring the malfunction to happen, or to have a malfunction happening in front of you. Repair the condition to get the electrical issue repaired, then unresolve the electrical issue, bringing the malfunction issue back so you can definately say this is the fix for my issue of the guages to jump, or intermittent issues. Dont forget the identical issues could be caused by different cables or parts failing. I want to bring up an issue of damage to the electrical system. As soon as a person who puts their hands on any part. they better know what they are doing. I read one message about one guy who pulled off a battery lead to prove or unprove the alternator was working. That is the biggest no no on newer cars with sofisticated computers. You never unplug anything while it is ever passing current or have voltage applied except turn off ignation then disconnect battery. This could be negative 1 condition brought on into the electrical system, causing future failure conditions, Causing other problems down the line. The floating ground is the issue, but not all caused by the same defective part. If the failing alternator ground cable fixed a problem for one condition it could be a no fix on some other car. Take the condition of an internal corroded wire connector, it could easily give the same malfunction, but maybe at a different connector. These connectors are squeezed connectors and can and will fail down the road if moisture is involved. If you make a new wire and connector use the same type wire, copper,or steel, but not mixed and solder if possible, but watch the type of flux used. Do not use plumbing flux. Seal the connector with a proper cover over the joint and use dielectric where it is bolted down. If you dont take all the proper pecautions then you introduce another condition into the senereo. Be careful. Like the neighbor who helps get car started when battery is dead and floating grown issues. He puts the jumper cabloes on wrong, blowing out the diodes or just alternator, then removes battery cables to see if car will run without the battery cable. he has introduced 2 negative issues into your problem making you now have 3 known issues or more you have to resolve. Some floatinf grounds could have more than just 1 fix. There could be corroded cable connectors with the wires, and corroded wire connector ends where they bolt to frame, bulkhead, valve cover, intake cover. you have to consider all connections and test them. You could just move a wire that has a faulty connection and cause it to function better than before you moved it. Of course later the wire you replaced looked like the the 2 week repair but the corrowded wire issue is still there. So what i am saying is to absolutely check every connector and improve it or fix it properly, use dielectric or some lubercant as well as a wire brush to clean all mounting surfaces, , dont use different metals together. Replace a known defective part with a known new or good one. Take resistance readings on parts and move wires,l tie them up. Sometimes there might be more than just one wire causing a problem. A damaged alternator replaced can be another damaged alternator later if the caused of the damage to the alternator is addressed. A low tickle voltage to the alternator will cause the alternator to charge with more voltage because the alternator knows that the exciter or tickle voltage could be lower because of a poor connector somewhere. when this condition exist replacing the alternator is not fixing anything because there is more then one condition causing all this. you have to get to cause of all this which means that you will have to be very familier with all the affected parts and wiring. Use jumper wires with alligator clips to bypass known grounds, and be extra careful in only working with a negative or positive polarity connections and not cross them. If you accidently spark something there is another fault introduced into the original problem. So I can see that either some people are introducing new faults into the system, working on the wrong failed ground area, have more than one problem, or dont know anything about careful diagnosing and repair. Ford has definately made some errors on mounting these ground wires, and could have done better. Other car makers are beyond this type of failures. Just use some type of lube on connectors to prevent corrosion and move on to improve their product. Check everything, recrimp, solder, clean, lube, protect ect.

I have a 2007 Ford Mustang that did this to me today I also change the alternator in the battery I was told that it could be a wired to the compressor and it also could be an electrical problem so he referred me to a guy at cartoon the guy cartoon really didn't want to give me any information they charge $90 an hour he really wanted me to just come get it checked check the wire to the compressor I pray this bless you for I am a female and I'm going tomorrow to have the wire to my compressor checked

I think that either you are confused or the person telling you doesn't have a clue. I really doubt that the wiring to the compressor can have anything to do with your battery and alternator issue. Maybe you meant the ground wiring to the alternator.

A chevy mechanic of all people resolved it you need to ground the altinator to the frame i havent had a problem after

I have been following this issue for a long time, I have a 06 4.6 GT Mustang with 70k miles on it, that I've had for several years now, here is my permanent fix to the full issues it had. The first thing i'ma say is that it has been some years since I fixed it and it never broke again on me. Check charging system, battery drain, and water leak permanent fix: My car battery died overnight My alternator and battery died twice My floor mats were wet after a downpour Car would die on me without reason Had crazy electrical gremlins all over. How i fixed it: 1-Replaced Battery and Alternator for new ones with 5years of warranty. 2- Upgraded the Positive and negative battery wires and added a direct ground from the alternator mounting bracket to the chassis and the battery negative terminal with a 2 gauge Ofc cable, And added an on|off master switch to the positive lead. 3- Added an exciter bulb since my pilot light on the dashboard doesn't excite the alternator. This way the alternator is being excited at the moment the engine starts and guarantees it will charge it steady and continues to do it at idle. 4- Added a permanent voltmeter where my cigarrete lighter was to monitor it as a new gauge since Ford volt gauge is inaccurate and unreliable. 5- Sealed my dashboard back panel, a common issue caused for a simple reason; 2005 to 2014 mustangs also known as S197, have a 2mm opening behind the firewall behind the AC filter that has been acknowledged by Ford and they released a detailed guide to seal it, you have to remove the right fended and take out the AC filters, the seal it properly (don't use silicone, it rusts and corrodes). This permanently fixed the water leak into the Smart Junction Box. 6-Removed the Shaker 1000 system, including the Ford Oem amps under the dashboard, removed the fuses for it and Installed an aftermarket full system. 7-Fixed a faulty wire under the dashboard that causes the fuel gauge and oil pressure to die. 8-Replaced All of the fuses in the SJB and the Main Fuse Box, and replaced the Starter and AC relays that became damaged by the overvolt spikes. 9-Cleaned and tightened all the engine grounding and the starter as it was rusted. 10- Added an underguard weather shield to the fuse box as it was exposed to the elements. 11-Replaced the Electric radiator fan and AC compressor due to them being damaged by the Alternator surges, and upgraded the wiring accordingly. The results: Voltage is steady at 13.5v - 13.8v at all times when engine is running Voltage is steady at 12.2v - 12-5v when car is left overnight (for more than 15 days I turn off the switch to storage the car and avoid the battery being drained) Alternator and Battery are healthy, the car no longer presents undervoltage, overvoltage or voltage sudden spikes or surges. The battery will last at least 15 days without being drained. No more water leaks, corrosion, wet dog smells, foggy windows or fungi (health hazardous) in the floor mats. The car starts immediately and will Idle without discharging. (Like any normal car) The upgraded sound system has a DVD, Bluetooth hands free and reverse camera. I retained the original door subwoofers as they are dual coil 4ohm at 80w rms, and I'm feeding them with an aftermarket amp. Trunk subwoofer is the same but at 100w Rms, I just replaced it for a 400w rms sub with its own amp. The upgrade to the electrical system Included upgraded wiring for the electrical radiator fan, damaged by the power surges, and also included a new AC comoressor due to the original one being burnt by the alternator. Last but not least, I had to replace the belt and bearings due to being damaged by the surges too. All the schematics are available at Ford's web page. This whole fix made the car reliable, took it from Anaheim to Atlanta and back and been using it to travel trough the country. 2 years and 30k miles later, the car has no issues whatsoever, the alternator and battery are healthy and strong, the floor mats are dry, and the legend goes on. This was the fix I came up with for my Mustang based on a lot research and a lot of help from posters on this forum that gave feedback on their cars. It's only fair that this information is shared to all of the Mustang owners out there. Currently I just joined the Pan-American Race and all I can say is my car is reliable now! Captain Edward Steinjolt

Same thing happened to mine I have a 2006 Ford Mustang GT V8 4.6 L three valve and had to replace alternator and battery more than four or five times after I got so frustrated I did it myself noticed pins on the alternator that were not grabbing correctly took me a while to find the exact pins and you must be careful with the positive cable when you're tightening the nut if you hear a click you tightened it too much and broke it from the inside but usually it's the plug either corroded oxidized torn out I changed the whole plug and put the pins in myself hope this solves your problem I'm also on Instagram as 305 Mustang gang

Oh man! Why didnt I find this thread before! I have had this issue on my 2005 V6 since 2016, have gone thru 3 alternators and 2 batteries and still the issue persists. Whats interesting is that when the interior lights are flickering the Check Charging System indicator remains off, but as soon as the lights stop flickering the indicator turns on, furthermore the indicator normally turns on when the car is at idle, revving the engine seems to fix the issue until when flickering stops for some reason and the indicator turns on permanently until the car is switched off/on again. Hate this stupid issue.

With my 2007 V6 it turned out to be the positive battery cable. It was defective internally and still passed a continuity test so I could not spot it myself. My mechanic saw a drop of melted lead and figured it out. Replaced it and the problem disappeared.

Okay I just bought a 2006 Gt mustang, about a week ago. This morning it died 4 times before I got it home. Radio flashed off and on before it died the first time. Turn signal got stuck. Windows got stuck on down. ABS light and traction light came on also. It’s been charging all day. If anyone can help me kinda figure out the issue it’d be greatly appreciated. Because I just bought it a week ago. Very aggravating that it’s already messing up. Thanks

As I wrote above, mine had very similar problems and it turned out to be the positive battery cable.

My car does the same thing as your car did. The difference on mine was the car amps would spike after 25 minutes of driving. Key word ( HELP )

The 2006 Mustang passenger side leak is caused, as someone else noted above, by tree droppings and fine garbage clogging the catch basin under the car's cowl. You only have to remove the plastic cowl vent on that side of the car, and reach in and clear the tray. I have removed the rubber bladder that allows water to exit down the firewall, to help the flow and stop the accumulation. Use a 20 ounce bottle filled with water to help clear the tray. Then stop parking under trees--especially maples.

I've contacted a lawfirm for a class action lawsuit. These issues and the money + time spent with nothing but failure has caused me with no transportation for 6 months. I had a very small poor family. This was the nicest vehicle we have ever owned. We all suffer from disabilities and mental Illness. I couldn't attend my mother's or grandmother's funeral because of this vehicle. I've been unable to afford any kind of travel to obtain a job as all the money we had was drained by failures to the attempted repairs to the car by both the dealerships, personal,normal mechanic shops and electrical specialists. I have a 4 yearold boy and I am 30. Ford ruined my life more then it was and before I die they will pay either physically or financially for what they have done with this fraud. You'll either get a class action lawsuit notification or something happening to the CEOs of Ford.

Just want to thank Steven M.. I’m a professional tech and worked for a couple of days trying to diagnose this issue. (My car, 2005 Mustang). In my situation, because of the bad ground at the Alt/engine to Batt neg my alt was seriously overcharging the batt. I saw 19.5 vdc on my scanner as a high point. As Steven has noted this is a feedback loop system where the PCM reads the voltage along with load factors, and sends the signal to the regulator side of the alternator which ramps the charging amperage up or down to provide the power needed back to your battery. Foolproof, awesome design. So then the ground gets lazy and the pcm is sending the alt a signal that the alt recognizes as low. So it ramps up wide open and consistently overcharges the battery-taking it out. Now the car won’t start and the battery tests bad so you replace it. Car fixed, pay the guy. Not. You guys that bought a high-zuit battery and are saying it fixed it, no, you fixed the symptom. An Optima and comparable will accept a high voltage charge without damage. You are still sending high voltage throughout your system and dumping it through all your other components, modules etc. “Why am I smoking stuff regularly in this car”? Why are my tail light sockets brown and burned up, weird? How do you think your dash or pcm likes this? They don’t, they are made for 12-14.5 volts. Why are your alternators going out? Because they are running at max load always. Why won’t the car start? Because the batt is trash from being overcharged. Why does my battery go dead after days......... So, install a new battery and a battery cable sized ground cable from the alt mount to the batt neg or body where the the neg cable mounts at the shock tower. NOW the problem is fixed. Mine is now running between 13.1- 14.6 volts and never strays. Next I’m fixing the SJB that the high voltage took out. Thanks Steven for being the smart guy in the room.....

Ok, running into this problem now with my wife's 2007 GT. Replaced the alternator and it ran fine for a week, however the check charging system and battery light never went out. I just drove it from Huntsville, TX to my office in the North part of The Woodlands (45 miles) with my foot in the gas the whole way and made it. It kept crapping out on my wife while she was in idle and I read on here that if of you kept it moving it didn't die. The mechanic here for my fire department said he ran into this problem before and the common denominator was after market parts. So I am going to put a Motorcraft alternator on this rocket tomorrow and see if that helps. We' ll keep you posted.

Battery #6 today for a ‘06 GT Convertible - bought brand spanking new -15 years old with less than miles - driven only May - Oct.

Buy an alternator from PA performance and be done with it.

I just got a "new to me" 205 Mustang GT. I work away from town for a f few days at a time and the car was parked for that. I went to go home and the battery was dead. Jumped it and it started really easily. started driving it home(at night with the headlights on) and while driving it at 110 km/hr the charging light turned red and it completely shut down. (engine died and all electrical quit working.) I went to turn off the headlight switch and it magically had all lights come back on(interior, headlights and dash). I tried to start it and it fired right up like nothing ever happened. It quit again about 45 min later and i wiggled the switch and again everything worked. I called my ford dealer and the parts guy told me that the 2005- 2009 years of the mustang had an issue with the headlight switches. Got one on order and I guess we'll see if that was the problem.

My 2006 mustang gt does the same thing that is in almost all these posts and I have the Shaker 500 radio and it makes this clucking sound when I open the door. Also my vent doors will make this same sound once in a while. I finally talked to a ford man that knows a lot about this and he said make sure the alternator plugs are all in and are good. My dash board lights come on intermittently but they do not mean anything so far. I mean it shows skidding sign battery sign and sometimes ABS light but they go away and come back on whenever they want to. But I have another problem and that is my check engine light comes on and stays on and the code shows lean fuel bank. The car dogs out over and over especially the warmer it gets. So my ford guy says the first thing to try is clean your mass air meter with alcohol and a cue tip. See if that will fix the lean problem. If not then you are looking at about 6 other things like fuel filter fuel pump spark plugs censors and there are about 4 or 5 of those and also vacuum leaks and a couple other things. So I am hoping the mass air meter does it for me. I am also going to put a ground wire from my neg. battery and alternator bracket and check all my plugs. If anyone knows some other things they have tried and they worked please post them. thank you