Hey guys,

I'm having an issue with the G and am hoping someone can shed some light on this issue.
First off, quick info: 2010 G37xS sedan.
Relevant mods:
-Grounding kit installed 5 months ago, no issues until now.
-Aftermarket subwoofer installed 5 months ago
**I do not have a voltmeter, so was not able to check the charge in the battery during the below mentioned issues**

Alright.... Sunday night I park my car at 11:30pm. Monday morning I try starting it at 7am: Doors lock/unlock, car starts and runs, but the only electronic item that worked was the navi screen. No speedometer/display, no climate controls, WOULD NOT shift out of park; even after using the shift interlock override. Temps dipped to just below 0 overnight (first bitter cold since last winters Chicago "polar vortex") so I figured it was just a battery on its last leg.

I finally get around to throwing a new battery in on Tuesday at 4:30pm. Car fires up like brand new; fully functional. Let it run for 30-45mins, park it.

Wednesday 10am: Dead again (exact same symptoms as Monday morning). It runs.... so I disconnect the negative battery cable while it's running and it dies (leading me to believe an alternator issue). I get it jumped, everything works perfectly again, but this time I take it straight to the dealer.

It has now been at the dealer for 2 work days, and they still have no idea what's wrong (when they started it this morning, they encountered the same issues I had previously). They tried blaming it on the aftermarket subwoofer and grounding kit at first, but these have been installed for several months.... I don't see them just now causing an issue?

I stumbled across this thread (https://www.myg37.com/forums/general...y-failure.html) which describes similar symptoms blaming the grounding kit for messing with the Battery Current Sensor.

I'm looking to see if anyone else has had similar issues, and what the fix was? Should I point the dealer in the direction of this Battery Current Sensor? And once fixed, remove the grounding kit?

Thanks in advance for any help.

 

I've had a grounding kit since 08. That's not your problem. However I would have recommended removing it before taking ti for service to take that bullet out of their gun.

If your car starts right up and runs, it's probably not the battery. Test the alternator just to be sure. I would guess body control module.

 

That's a good point. Too late now tho. Cars been there for 4 work days now and they still can find the issue. Thanks for your reply.

 

A few people had a problem with a faulty emissions valve draining the battery. Another member had his problem traced back to the trunk light not turning off. Although your battery seems to be dying rather quickly, you can still check out the thread for reference if you haven't yet done so:

https://www.myg37.com/forums/audio-v...ry-issues.html

 

Thanks for the info guys. Car is still at the dealer... And was wrecked by the guy plowing their lot this weekend. Still have not been able to determine the issue as of yet.

 

You can obtain a free one at Harbor Freight with a coupon

You can check the condition of the battery cells with a battery hydrometer.
About $10.00



Telcoman

 

Dealer says it's a combo of a loose negative battery cable and a instrument cluster electric issue, needing to be replaced.

Hopefully after this $1300 dealer trip I'll be back and running..... AFTER the body shop finishes their work, too, of course.

 

fyi for the future. you cannot disconnect the battery wires on modern cars while the car is running. you will at best fry the voltage regulator and at worst fry the bcm.

 

Got the car back last week... bumper and headlight repaired from wreck. New instrument cluster, new negative battery cable. Dealer is adamant they tested every electrical connection and module in the car and those were the only issues found.

4 days later.... same starting issues. Let the car run for 10 mins, and problem fixed itself. While on the way to dealer... brake light, traction control light, VDC light, seat belt light (dim) and CES lights all came on.

Waiting to hear back from them still; it's been 2 days. I can't afford to keep throwing money into this, but dealer says all of the other items you guys suggested above are not the issue.

My plan is after getting car back from the dealer, get all electronics back to stock. And see what happens after that. I do have a DDM HID kit installed in the fogs....and Diode Dynamics LED's in the headlight housing and tailights... but I really don't see these causing a major electrical issue like this.

 

You didn't mention this before. That's where I'd look for the problem. Did you install this yourself?

 

Yes I did it myself. I didn't even think of it as they are lighting components and have been on the car for many months without issues. Unless cheap wiring is faulting.

 

You had to tap or splice into the car's wiring to install the fog lights, correct? Try checking all of the wiring and connections.

 

It was plug and play, and I also sealed all connections with electrical tape as well. The more I think about it, the more I wonder if it's this cheap DDM kit. Regardless of what the dealer discovers, I'll probably just remove the kit anyway and go back to LED fogs.

Just odd to me that a lighting issue could cause all this. But I guess it's possible with all these electronics nowadays. Thanks.

 

Update:
Dealer refused to diagnose the problem with aftermarket wiring and lighting in there. Spent a few days getting the car completely back to stock. Just heard they were apparently able to successfully diagnose the issue this time as the AC Auto Amplifier; located under the radio unit.

Part will be replaced and car is being taken back to the body shop for repairs on other accident damage I discovered.

Q50S loaner is nice tho. You guys can expect a part out coming in the next few weeks as I will most likely be finding myself in another ride within the next month or so.

 

Glad they seem to have found the problem, and thanks for coming back with an update. I do like the Q as well! They haven't given me an S yet, maybe I'll see if I can talk them into it should I need a loaner on my next visit