'02 Jetta won't start....security system issue??

His best bet,is to remove all components he installed,,leave the battery un hooked for 8 hours,and try to start it..He may have triggered the alarm,or hooked power to a lead,connected to the alarm,it"s self..Been there,done that!! Hope this helps....

i do not think it is an alarm issue, if it is it deactivates when you actuate the remote. if it is the immo it has a light with a car and a key flashing. and the car stars and shuts down again. The first thing i need to know is if the car starts, or if the engine turns. i would recommend to check the fuses on top of the battery and on the drivers door. let me know if this does not resolve the problem

If the car starts but immediately stalls it's an immobilizer issue,as stated it's a picture of a padlock and key if it's flashing then there is an issue.unfortunately if it is the immobilizer you are going to a VW dealer to get it taken care of.all communication issues are done on a secure line going right to VW AG .Check all of the fuses and again as previously stated the fuses on top of the battery .sometimes stereo installations are left to professional shops.

Tried leaving the battery disconected for 8 hours but no luck. I checked and it does not have the padlock and key flashing. Checked all fuses and didn't find any blown. I noticed that after cranking the car for 15 seconds or so that the temp light and the oil light start to blink and chime. Is this a clue? Also pulled a plug and expected it to be wet as many times as we have tried cranking it. Dry as a bone. Might be normal with fuel injection but I'm not sure. Any chance this could be a relay issue?

Ok,let's get to basics here,a car needs three things to run ,spark, fuel and proper timing.as you have pulled out a plug ,take it one step further,install the removed spark plug into the end of the plug wire,ground the end of the threaded portion of the plug ,have an assistant crank the car over and check for spark,if there is spark but still no start,next is fuel,this may get a little more involved,not being sure of your abilities I will describe what you need to do next. Under the rear seat you will find a metal cover under the carpet on the right side,three Phillips head screws hold it in place, remove the cover, you will see an electrical plug on the fuel tank sender,there is a green wire with a yellow tracer this is the fuel pump power wire,using a test light or a voltmeter ,while cranking you should have 12v approx. On this wire,if no there is a power supply relay under the drivers side of the dash,as I do not have any service information in front of me I can not give you the location number or the code on the relay,usually gray in color.check these basics out and let me know what you find.

Remember to ground the plug so it can spark. Since this was after the music was installed check to see what original cables he cut or connected to the music because it can be any current missing from the ecu or anything that has todo with the engine. I do suggest to go with garage man and check for fuel and spark first to see what is missing

garageman, Took your advice and checked the power at the fuel pump connector... 1.6v when disconnected from the fuel pump. Installed a new fuel relay and got the same results. Checked the voltage with the conector on the fuel pump and got zero volts. Continued to check the voltage and all at once the fuel pump cycled and I got 12v on the meter. Started the car multiple times after this...10 times or so and then the fuel pump stopped cycling and the car wouldn't start. Checked the voltage again with the conector removed and got 1.6v. Placed the connector back on the pump and got zero volts. At a loss since this seems to be a very sporadic issue. Any thoughts? Thanks for the help!

At that point I would be taking a look at the electrical portion of the ignition switch,you can get the covers off of the column without removing the steering wheel,I would drop the lower cover and pay close attention to the plug and the connectors,I have had them melt down,no reason they will just let go,try to sort of wiggle the key and see if you get the voltage back to the fuel pump.

you know just rereading through your post, where did your boy hook into for power. For this subwoofer system?VW also uses what they refer to as a load reduction relay,this acts sort of like a temporary switch to only allow the starter and the ECM to get power under cranking,with the key on if the switch is ok I would be reaching under the relay panel and doing a wiggle test to listen if anything is "clicking" on and off,I would be back tracking the wiring for the stereo very closely.

Garageman, Reached under the dash and found that when placing a slight amount of downward pressure on the fuel pump relay that the fule pump will cycle with the key truned on. The car will start with the relay held down. Push the relay up and the fuel pump will not cycle. Push the relay up after tha car has started and the car shuts off. Also noted that when pressing the fuel pump relay down and the key turned off or with the key removed that several dash lights (check engine, temp, oil etc) will light up and chime. Saved the best for last though....when pressing down lightly on the fuel pump relay you can turn the key to the off position, remove the key from the ignition AND the car will continue to run! I have owned alot of cars over the years but have never owned one with this issue. I also inspected the wiring to the ignition switch. Pushed, pulled and wiggled and did not find any issues with the wiring. Now looking at the relay block that the fuel plugs into to see if I can find loose connections. Also trying to determine if there is an issue with the ignition switch since the car won't turn off unless the fuel relay is pushed upward. Might be our first and last Volkswagen!

In order to make it little easier for yourself,if you remove both of the plastic knee bolster covers and also remove the metal reinforcement beam right behind ,its only held on with four or five torx head screws.It will enable you to see better what you are looking at,rather than standing on your head,trying to figure out the relay block.Also on the blocks ,where they go into the mounting bracket,you will see a couple of release tabs that will allow you to get the block out and reall be able to give it a closer examination,but I think you have it narrowed down,glad to be. Of help.Bruce,AKA the garageman

Thanks Bruce. I really appreciate your help in sorting this out. Do you think the ignition issue is seperate from the fuel relay or is the loose relay causing the ignition problem? Thanks again. Brian

I think that if you get the power supply/ fuel pump relay issue sorted out first then see if the ignition switch sorts itself out,but you need to get it down in front of you so you can take a close look at it ,I would be looking at the grounding side of the relay very carefully.VW uses cluster grounds that are in the close vicinity of where you are working

garageman...looks like we got to the bottom of this issue. Pulled the relay block , opened it up and found that in the process of my son trying to hook up the stero he cranked on one of the nuts holding a power wire (bottom of the block). The nut and wire were attached to the contacts in in the block which twisted and contacted other contacts in the block. Strightened everything out, put the block back together and she fired right up. So far so good. Thanks again for all of the help in tracing this down. Brian

Brian ,glad to be of service,any time there is a problem with a car ,the most important question you need to ask is this,What was the last thing fixed on the car?Most times just by some keen observation you can find the problem ,not saying that this is a 100% but it works for a lot of issues.VW is not a bad product but they definitely have there own ways of doing things,be well Bruce

I am having the same problem. If my battery is bad can it cause this problem? I tried all of the things mentioned so far. Can anyone help?

In order to check a battery properly it should be at least 75% charged.That way you will stand a chance of getting accurate readings,the new battery testers work by using at the internal resistance of the battery.however a good old fashioned load test followed by specific gravity readings of the individual cells is the most thorough way to. Make certain of the batteries state of health.You do not mention if you are in a hot climate or not,heat will be a batteries enemy.and make sure the the charging system is putting the proper voltage to the battery as well.general rule of thumb is not more than 14 volts and not less than 12.6 volts.

I live in New Mexico so its hot but not to hot I would think. I was told that if a cell within the battery is bad there is a component on the car that can detect that and would make it so that the battery was not giving enough cranking amps. Is this true?

that is where the specific gravity test will come into play.Each cell if the water to acid ratio is correct should have a reading of 12.60 to 12.75 if you get any reading that is much lower than another cell then you have found your problem .How old is the battery you now have?

The battery I have now is less than 6 months old. So this can cause a starting problem? When i crank the car I am getting 0 volts at the fuel pump when its connected....Why could that be?

Do you have power at any other time? Have you checked the fuse? Have you changed any electric wiring on the switch? If the battery has enough voltage to crank the engine the battery is not the problem

You should check the relay for the pump. It is the same relay for the ecu

Replaced the relay no change, went to autozone and they charged my battery back to full100% and the car started I ran it for 5 minutes and tried to start it again and got nothing....

The giveaway for an immobilizer issue will be the security light flashing on the instrument cluster,it's a yellow picture of a padlock and key.

Check the fuse block on top of the battery,make certain that the strip fuses are all in good shape and none of them are blown.The heavy gauge black one on the very end is the alternator feed wire,be certain that the wire end is not broken at the terminus where it bolts on.not very common but I have seen it happen,if it's broken or corroded the alternator will not charge the battery properly.

its' true the box on top of the battery usually breaks down mostly on the alternator/Starter cable (the black one on the end). If the inmo is activated vw autos start and then shut down, so i don't think it is a key issue. you need to check what is missing when the car fails to start. Fuel, spark or what fails? this is the first you need to know to get to the problem.

When the car won't start there is no power to the fuel pump

I would be looking at either the electrical half of the ignition switch or the load reduction relay.

Just found out that my battery I had was barley making minimal requirements so I got the one that was recommended

So left the battery unplugged all night then went and hooked it up and the car started and ran for about 2 minutes then shut off by itself. The only light that was showing on the display other than the brake light was the battery light

you may have an alternator problem. after the car stars it doesn't stop unless the alternator is not producing voltage. check with a multi tester the voltage while the car is running, the battery voltage must be at least 12.80 up to remain running. the normal is +/- 13.50 to 13.85 with all equipment off and 12.90 to 13.30 all equipment on (with a charged batt). Check this first to resolve your problem.

found a broken wire by the battery my car works thank you

Two times in the past several weeks I have turned the dashboard light switch on in my car only to not turn it off when I exit the car to go to work. Eight hours later, my battery is drained so I get a fellow employee to give me a jump. In doing so, it somehow 'resets' everything and now the car alarm goes off every time I start the car up. I lost my remote key (I will refind it when I move out of my house I'm sure) and only have the valet key. The trunk is closed (as it should be) and the key will not open up the trunk being its the valet and sticking in the driver's door lock will not resolve the problem. BYW - I have a 2000 Jetta. What I have done before is disconnect the battery cables and touch them togather for a good 20 - 30 minutes while I drink a couple beers. I then reconnect the positive first then the negative next, tighten them down real good and turn the car over. This somehow resets the car and everything is back to normal. The car might run rough but as I drive it several miles it seems to work itself out (actually runs better if you asked me than before). Oh yea I unlock the trunk prior to doing all of this just to have it ajar. If I disconnect the battery real fast and reconnect in a minute - it seems to allow me to open the trunkk up even though the alarm will go off for 45 seconds. For some reason I get lucky to resolve the issue by fooling around with the battery for a good hour or so and so far it seems to work for me. Mind you - it is a pain in my rear doing so and I worry that things will not work out as planned but the car gods seem to allow me to get by. Give it a try if either the alarm keeps sounding or you are being 'immobilized'. Both have happened to me.....

oh yea - the car radio will need to be coded. I plan to put a piece of duct tape over the damn switch so I can't turn the lights on during the daytime when I don't even need them! I never said I was smart and admit I'm an idiot like the rest of us

That happened to me once. My car did not want to start in spite of the engine was sounding right. when trying to start it. Battery was o.k, stater o.k as the rest of components related with the start of my engine were perfect, just that i was being immobilized. i was turning my key to start the engine it seems that it want to start but not luck. so i placed the key on the ignition turned it like i just want the radio to be powered for about 30 minutes and the immobilizer reset my security system allowing me to start my engine.

Okay so i got a 2002 vw passat and I unhooked the battery put it back on and it won't start all dash lights come on battery charged never had this problem before checked everything I'm lost idk what to do please help

Did you plugged back all the cables? Is the battery charged?? You need to check that first

Same issue with a 2002 1.8 t. It will start then stall within 100ft of driving sometimes. Only will restart when jumped. Clicking sound by dashboard and resets clock and other items.Once jumped it drives fine and then will do same thing again next day. Battery and alternator were checked and are fine?????

That sounds like the main relay, it sounds like a click under the dashboard. I've had this issue could be a cable, the relay itself the ecu. For this you will need experience to check this, there are some continuity test and some disasembl

OK. Here's a tricky one. Car turns on, but doesn't start. Although after a few attempts it'll start. My key sometimes unlocks and locks the doors, however seldom unlocks the trunk. Any ideas?

I have a 2002 Jetta that's not starting , not getting spark or fuel it just cranks , I've replaced fuel pump battery and I've tried all the you tube tricks , thinking it's maybe a security issue ? Also I. Had issues with original dash cluster having lights burned out so I tried to replace it with a new cluster , the new cluster didn't work so I put the old one back in and ever since then it won't run? Any help would be great thanks

2000 vw jetta starts then dies then won't start period it just cranks over and over again has spark and fuel but no power to fuel injector

i have a 2002 1.8t Jetta, yesterday my battery died so i took it to autozone to have it charged, they told me it was a bad battery so I bought a new one, now lights and dash all turn on but engine wont crank no sound nothing, alternator starter everything checked, any advice?

Can someone help me! I have a friend with a volkswagen jetta 2002 1.8t her car was find until she run it out of gas one day. Next day she put gas on her car and it didn't start. The car tries to start but then it turn off. Her mechanic says is the dash cluster but they can't fix or have not been able to fix it. She is willing to give to me for $300, is it worth it to buy it???

I have a 2001 jetta we have bypassed everything but the people that we bought the car from took the factory radio out to install a different radio and car wouldn't start u could at the time hear a toy machine gun

2003 Jetta 1.8t. When cold the engine cranks but will not start. As soon as the weather warms above 32 degree's she starts right up. If the temp drop she will not start. Just turns over and over.

My 02 Jetta does the opposite. Stops gong down the road randomly. If I shut it of or if it shuts off by itself it don't start till almost the next day it's just usually worse when it's warmer out side....have read all these stories and none of them seem it. Could it be the MAFS or the ignition coil pack?