G6 won't crank

Ok step by step. Security light not on so you know it's not ignition nor key. When you attempt to start car what happens? Does it Crank and no start?

Are you getting Sparks? Power and pulse to injectors? Fuel to engine?

It does nothing no crank whatsoever I hear no clicking other from the relay ... the check engine light is on which it was not before

That check engine is your hint. Check to see if you get power to the signal wire at the starter. Here's first step. Pull starter relay check if your getting power there. If you are place key in ignition on with accessories on and have someone turn key and see if signal wire getting power at the relay and work your way down. If your not getting any you may have an interrupt switch or fault at ignition

I’m having the same issue. New battery, gas in tank.. I go to start and everything seems fine but when turned all the way, it won’t crank at all, automatically locks the doors tho.. also, I have a convertible, and when I go to close the doors, the windows no longer roll all the way up. I checked for codes and p0452 came up, I’m not sure if that stops it from cranking though..

Where is the starter relay located at

The instrument panel fuse block is located on the passenger side of the vehicle, on the lower portion of the instrument panel console near the floor

Here is the engine compartment fuse and relay panel listing

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Lastly 4

My car does the same thing battery fine full tank and I changed the starter probably like 5 months ago now so I don't understand why it won't start

AllwhiteG6 sorry did not see your comment as I work for a automotive shop and run busy from time to time. But your code is either an Evap (Fuel leak) but does not stop your car from cranking!

It seems as there is a common issue with electrical on the G6. Now we know you all have the same issue. Did anyone trace to see where you are losing power? Simple steps follow these steps and you eill find fault

Check power voltage at battery 12v+ Check power leaving ignition 12v Check relay has power entering relay and leaving. There is a signal wire that send power to starter and a ground on that relay make sure all are there. If you have to jump it to start car use jumper wires to start car. Check starter signal wire to make sure its getting power if it is (Using a 12v test light) and it lights up your starter maybe burnt out.

The starter is literally 2 inches from the catalytic converter on the 3.5 V6. (2006 G6 GT) Once the engine gets hot (catalyst) the starter heat soaks and will not crank until it cools down. This is my experience. I have since installed a heat shield and the occurrences have reduced.

gm has been producing lighting harnesses that are made backwards, the harness located directly below the fuse box. had to manually switch all the wiring back around. every. single. wire. that can work, or if you grind off the three tabs, itll fit backwards with zipties.

I have the same issue going on. I went thru 3 different starters so I know its not that. It turns on at times but sometimes it doesn't. Thus is really irritating.

I also have this issue I have replaced the starter, ignition switch, all relay's and battery. It's the 3.9 and also seems related to heat I live in Phoenix so when car gets hot and ac is used car won't restart once turned off. Full power at battery relays and starter I think it's computer related. Only thing I haven't changed

i have the same issue what was the problem

So, on the V6 engine, the starter is almost touching the catalytic converter(which is super hot). When the starter gets too hot, the solenoid will not engage and the starter wont crank. Also, the low pressure oil switch is right above the starter, mine sprung a leak and covered the starter in oil, that may have accentuated the problem along with the heat from the cat.

I put some header wrap (fiberglass tape) around the cat and also a heat shield on the starter, It hasn't got very hot in LA yet but i havent had the problem since. Ill find out this summer.

I have a 08 Pontiac G6 4cyl 2.4l I’m 17 and can do most work on my own now I am having same issue I turn key all lights radio everything comes on starter clicks but will not crank now when it does start it fires straight up like it never had an issue now I started with battery I just figure it was a bad connection due to how it would be a hit or miss and everything had power and if I play with it for some time it would start so I replace battery problem did not go away and my terminals would not tighten so I replace them also then I moved To my starterwhich is located in the front on my car my cat is in the back so I don’t think the cat it causeing my issue considering they are not by each other now I did my whole exhaust front to back one morning and decided to go ahead and replace the starter now the problem still occurs then I went to fuses all good there then I go to the ignition switch Replaced it key and lock cylinder and problem still occurs I now am lost in space with no helmet I have no clue what to do and I really need help my car has not started in 4 days just clicks now and my battery is not even 3 weeks old now this has caused me to lose my job at a great car dealership can someone please help me figure this problem out

Fixed ours by cleaning ground to fuse box. Few scrubs across with brush to remove gunk and started right up.

Mine does the same but if you open drivers door a close the car will start,cant figure out whats going on.

Side panel of center console wiggle wires started right up

If ur battery is good n fully charged..Take positive off battery for 15 mins. Reconnect n should start right up... At least mine did. Gonna check into it more so I hopefully don't have to do this every time but will let y'all know if n when I do figure it out. Thanks, Tina

Hi Tina, Thanks for your response. Have you tried just letting the car sit for 15 minutes instead of disconnecting the battery? I am just wondering if its a temperature/time issue instead of an electrical/time problem. -Hector

Hi, Mines does the same exact thing, once you drive it along distance, it will not restart back until for 3 hours or more... My husband has change starter, battery etc, and still does the same thing...But Today since it's been raining, cut it off, fires right back up... Have anyone found the solution yet?

We have the same problem. My daughter drives it to work, and has to leave it every day.. we go back that night and it starts right up. We have replaced the starter, ignition, alternator, wiring and wiring harness. Thought the problem was the starter getting too hot, so we wrapped the starter with a starter heat wrap, but it's still doing it... Should I try to wrap the catalytic convertor also?? Ugh... I hate this car.. but I'm too pissed off to quit trying to figure it out..

Wiggle the main wiring harness coming from the fuse box underneath the hood driver side

Rock it multiple times to engage the starter to the engine.

I have a 06 g6 gtp.....same problem & it was in the shop 8 days & they couldn't figure it out but something super wiierd happened the other night when i keep tryin to get it to crank till the battery died & as soon as motor stopped turning & my starter clicked a few times i turned key off & on & it started without starter spinning

Wiggle the big wire bundle by the fuse box under the hood ... Play with it while someone else trys to start it..

Do ANYONE know what could be wrong with my car it starts fine in the morning starts on my lunch break soon I get back I my car want start battery good alternator good and starter

Your starter is hot let it cool down for a while then it will start.

A month ago my battery went dead..it was a very hot day in Michigan..when checked the battery we were told the cells were dead so purchased a new one car started right up..i also knew i needed front brakes..a month later while still on i could not shift the gears as if the gear shift didnt stop on park reverse or drive..so i pulled into parking space and pulled the emergency brake..then turned off the car..a few hours later i went out to see if i could placed in park and all lights came on but wouldn't turn over..we changed the brakes however we then noticed the lock message come across the radio so we disconnected the battery for over 48 hours and stop nothing but all lights..my bf checked the fuses under the hood and also in the rear but not inside the car just yet and let me add another that's going on with the car..without really knowing which one it could be sometimes my car heats to over 220but bit to over heat to shut the car off but I'm wondering if needing a thermostat or water pump would cause it not to start..please help..

Take screwdriver touch top bolt to bottom with key turned halfway should start up

It's the neutral security system. Put your car on neutral and it will start. You will still have to replace the neutral security system.

I found out wat the problem is my car does exactly wat you say its doing well its not good news pontiac g6 2008 mines was my computer in my car.all the stuff i bought starter battery wires post alternator starter wire relays and the hole time it was my computer damn theres your answer im 100 percent postive

Could be the starter. I noticed problems with my 2007 G6 GT; the remote start quit working, the automatic locks, cruise control and even both the reverse lights weren't working. Then, a couple months later, the car wouldn't start. All the lights came on, even the headlights but it wouldn't start. It was the starter. Had it replaced and everthing is working again!

There has also been two recalls for the g6 plus many others having to do with the wiring harness I believe. Might double check that

Hi i have a problem with my 2007 g6 it takes turning the key 3 or 4 times to start and there a gas smell when i turn it off... Can anyone help me

It’s the computer not recognizing the starter we have the same issue, Once we take the positive off the battery to reset everything it will work again for a few weeks. The computer isn’t recognizing the new starter we installed- Very frustrating and a lot of money put into this thing to figure out this was the problem.

Let me just add to the possibilities , and what happened to my G6 G6 coupe convertible. 2008 with 3.5L. I also had replaced the starter around a year ago. So it was doing the exact same thing as you all, click upon trying to start like it had a dead battery, but the instrument panel was all lite up bright and not acting the same as if it were dead battery. So i go and start wiggling the wiring harness wires around the ECM, and i see that the ground wire attatched to the frame is loose. I tighten it up and the car starts right up! So, just gonna keep an eye on it. Not driving it much since COVID, but will try it out several days.

Okay so, I came to this forum looking for an answer and didn’t find one... found a really good mechanic and they told me my timing chain is broken so 9/10 your timing chain is broken I just got a whole new motor

We had the same problem, lights come on, battery fully charged. It was a pinched ground wire to the ECU

For those people who have found their G6 won't start when it's 'hot'... look to the main fuse block under the hood, next to the battery. There is a good video on YouTube that explains what is happening. In a nutshell...there is a copper wire INSIDE the fuseblock that has cracked from heat, and when the wire gets hot, the crack has a larger gap and loses contact. I'm in California and mine does it when it's over 100 degrees out and it sits in traffic or idling too long. Once it cools down(up to 3 or more HOURS) it will start right up. I thought it to be the starter...ignition...battery...but it's NONE of these. Watch the video and you'll understand EXACTLY what the issue is.

I had the problem of mine not starting, too. I had checked the starter, battery, alternator, relay and the fuse. All were good. I was afraid it was an issue with the computer. I had one last thought, so I bought a book with the wiring schematic. The only 2 things I had not checked were the grounds and the switch for the car not being in park/neutral. While checking the grounds I found that where the shifter cable attaches to the transmission. The cable was not attached and the car was not all the way into park. This will keep the car from starting. Once I put the car in park the car started.

I'm so utterly shocked that I had to post this... I tried everything from multiple sites about a g6 always starting fine and suddenly .. single click. So I started trying the more "out there" suggestions and ran into "Rock it multiple times to engage the starter to the engine." (From CHL12) and thought.. "well that's laughable" and later.... "well I've tried everything else right?!?!?!" - what do you know the car started right up. - I just kinda stared at the back of the garage bewildered for a while but I gotta throw more props his? way than just finding it helpful.

My son's car just did this. The ground cable on the starter was loose.

there is a recall for the bcm install this will fix your problems Recall Title: BRAKE LAMP MALFUNCTION Recall Description: General Motors has decided that a defect which relates to motor vehicle safety exists in 2004-2012 Malibu, 2004-2007 Malibu Maxx, 2005-2010 Pontiac G6, 2007-2010 Saturn Aura vehicles. On these vehicles, over time an increased resistance can develop in the Body Control Module (BCM) connection system and result in voltage fluctuations or intermittency in the Brake Apply Sensor (BAS) circuit that can cause service brake lamp malfunction. As a result, the service brake lamps may illuminate when the service brakes are not being applied, or may not illuminate when the service brakes are being applied. Additionally, cruise control may not engage. If cruise control is engaged, additional service brake pedal travel may be required to disengage it. Service brake pedal application may not be required to move the shift lever out of PARK, or additional service brake pedal travel may be required to move the shift lever out of PARK. Traction control, electronic stability control, and panic braking assist features, if equipped, may be disabled. Service ESC and/or Traction Control tell-tales may illuminate with this condition. Safety Risk Description: These conditions may increase the risk of a crash. Repair Description: Dealers are to attach the wiring harness to the BCM with a spacer, apply dielectric lubricant to both the BCM and harness connector and on the BAS and harness connector, and relearn the brake pedal home position free of charge.

My uncles says its a bad ground wire.. Ive been to a shop twice had it running then bam. Nothing. It gave me a lot of different codes but thats because of the disruption in the current. It cant get a good reading. So check the harness grounds.. Mine are connected to alluminum instead of steel which conducts way better.

Thats why many mechanics cant figure it out. Cause the computer says its this or that when its just a bad ground. Its so simple, so before you go replacing parts try that. 75% of you all will be amazed

Mine was a faulty connection between the CPU. It is near the fuse box, a silver looking box with 3 harnesses running from it. I used duct tape to tape the connection. This is usually a fuse box or CPU issue. Also recall on fractured transmission wire is something to look into. The factory radio must stay in these vehicles with RKE mode on. The security system is connected to the radio. Will cause issues with starting also because the system thinks the car is stolen.

05 Pontiac g6 gt. When it doesnt start I wiggle the red square wiring harness plugged to the fuse box on passenger side. Is it the harness of fuse box that's bad

I had the same issue- I read every forum online just about - checked the entire electrical system - unplugged /cleaned / and replugged every connector associated with engine start. I scanned the vehicle with a snap on Apollo d9 and it wouldn’t read the ecm. So I went to transmission data and that’s were I noticed the car thought the engine was idling at 550 rpm- with torque around 30 - but the engine was off. Also the fuel tank was 3/4 full however when no crank no start occurred the fuel gauge read low fuel . I went and purchased a used ecm from the local pull apart - from a 2007 g6 gt. Mine is a 09. Had it reflashed with the current software for the cars vin - and first try fired up. Still firing up every time . GM rep said it’s a known issue for those cars ass well as a few other gym’s. Just wanted to share my fix-

well that didnt last long... have been troubleshooting same issue now 3 weeks . frustrating

It sounds like everyone has a different case, but if your car intermittently starts and will start mostly when cold, you're having atarter relay control circuit, look that up and go from there, very common problem on g6 g5 malibu cobalt