GXP Charge System Failure
Thread Starter
Teching In
Joined: Feb 2010
Posts: 3
Likes: 0
GXP Charge System Failure Brand New Battery. Charge system Failure message displays, but if I drive the vehicle it comes and goes away. The blower motor fan also comes and goes on its own. Had problem before and replaced the battery which fixed the problem until now.
11 Second Club
Joined: Nov 2001
Posts: 300
Likes: 1
From: Central Florida
That sucks. Got an amp clamp and a multimeter handy? Put the clamp on the fat red wire and check the generator output. Sounds like it's on the way out. Don't let it take out the new battery.
Staging Lane
Joined: Nov 2010
Posts: 85
Likes: 0
From: Carol Stream, IL
That's wierd, I had the same message come on my car a couple weeks ago and I quickly switched to the Voltmeter on the DIC, it read something like 15.8V or something and gradually went down to like 12.9, then leveled out. It's been fine eversince, tho, and I've driven it maybe 1k miles since then, too (even took it to the track!). My car's battery is maybe 1yr old but as far as I know the alternator is original.
sounds like the alternators not charging properly . if your interested i have an high output alternator for sale. because the factory junk only goes so far, i dont like dimming lights and after i swapped it never had the problem again even with a few subs and amps.
Teching In
Joined: Sep 2011
Posts: 16
Likes: 0
I had the same problem with my 2005 Grand Prix GXP. Look on the DIC and see what your voltage reads. Mine was reading 17-23+ volts, which is way higher than normal. I put a volt meter on the alternator output and the battery and confirmed I was getting the correct amount of voltage in both places. After I got a wiring diagram from the GM dealership, found out the BCM (Body Control Module) is responsible for monitoring the voltage and that is what was bad...it was detecting the incorrect amount of voltage. Took it into the dealer to have the BCM replaced and problem was solved. I would have tried doing it myself, but I heard the BCM needs to be programmed properly or else you can run into other problems. So I figured, to bite the bullet and let the dealer do it.
Hope this helps someone else.
Hope this helps someone else.
