Hoping the community can lend some insight here--my 2010 G37x sedan has taken to playing dead on us from time to time when we try to start up. The car goes totally dead--can happen first thing in the morning, after stopping for an errand, after sitting for a bit. Everything mechanical has been checked--battery (less than a year old--and the old one was charging fine in any event), starter, amps, voltage, etc etc. Then, just connect jumper cables and BAM--comes to life and starts right up. Anyone else have this issue?

 

I'll move this to this folder for specific replies.
G/L

 

I know you listed checking the battery, but have you checked the battery connection. I had a problem where the negative battery terminal kept getting loose and would disconnect sometimes after driving hard on bumpy roads...the terminal got stretched out and needed a shim....someone else mentioned having to shim their negative terminal too but I haven't heard of anyone else wit he problem

 

So when you say the car goes completely dead does that mean your dash doesn't light up at all? I had an issue a while ago where my G wouldn't start from time to time and started getting worse. Turned out that the starter had dirt built up in the connection and was causing it to arc then eventually got bad enough it wouldn't catch at all. Cleaned up the connection and everything is back to normal. If your dash doesn't even light up then it leads me to believe that it is a battery connection issue. Hopefully it is that simple but you say you checked it and the starter so who knows. Sometimes it's the simplest thing.

 

check your battery post connections first. if thats good you need to load test your battery and i'm not talking about one of those handheld digital battery testers that just checks the surface charge. you need to use a carbon pile and put a hard load on the battery and check if its capable of holding charge. just because the battery is one year old doesn't mean squat. plenty of shi tty batteries sold and people tend to buy the cheapest one on the self or whatever the parts counterperson pushes so he can get bonuses when he hits the quota. since you stated the vehicle starts right up when it is jumped its a clear indication your problem lies with the battery which is the source of power for everything in the vehicle.

 

^^^^^^^^

What he said!


For about $10.00 go purchase a battery hydrometer and check the individual battery cells for a possible weak cell not holding a full charge.

Full charge



Half charge



And invest in a digital voltmeter to check alternator voltage output



And what was the CCA rating (Cold Cranking Amps) of the year old battery?
You can buy cheap ones rated at 480 CCA's and better more expensive battery's rated at 700 CCA or higher.

Telcoman

 

I recently started having this problem with my 2008 G-37 coupe; battery,alternator & battery connector were all replaced a few months ago. No problems until last week; went to start car & it was totally dead key fob & all. After jumping battery it will crank right up and will be fine all day and sometimes multiple days and then it happens again. Took to dealership and battery and alternator both tested fine. Going back to dealership tomorrow and will ask them to check for dirt build up in starter connection as mentioned above (Thanks for the tip BHunts). Hashim, any luck with finding out the problem? If so, please post outcome if you don't mind.....I'm curious. Hopefully, I will have some resolve to share after tomorrow.