Current leak through interior lighting kills battery
2006 GTO, M6, owned since new, 65K miles.
My car has been very trouble-free but an electrical gremlin has gradually developed. About a year ago I noticed that the battery began dying if the car wasn't driven for a while. Its gradually gotten worse and now the battery is dead after only a couple of days. The charging system seems fine, and checking with a volt meter the battery has a full charge after driving around for a bit. I replaced the battery and that did not help, so I checked the current draw at the battery and it is pulling .140 Amps with everything off and the key out. I opened the interior fuse box and found that if I pull the interior lighting fuse it drops back to .01 Amp. So it looks like I have a current leak through the interior lighting circuit. I checked all the lights including the trunk and everything seems OK.
The only mod I've made is installation of a Pioneer AVIC head unit a few years ago. I used the correct wire kit, soldered all the connections, etc. and it works perfectly so that shouldn't be an issue.
Does the circuit go through the BCM after the fuse? I checked behind the glove box and don't see any signs of abrasion on the wire harness (though I will protect it for the future.)
Any ideas where to look? Is an interior lighting circuit diagram available?
06 Impulse blue, M6, 17"
69 LeMans vert, stock-looking 455-powered "sleeper"
74 455 TA, HPP magazine cover car