Thread: Weird charging problem

Reciently I noticed a few problems with power levels in my 04 grand prix.

I was sitting at a light about 2 weeks ago and The DIC popped up and said "Charging System Failure" and there was a big battery displayed as well. It only happened for about a second. I quickly changed over to my voltage and it was sitting fine at 13.8 volts.

A few days later we got some really cold days and I always let my car warm up for a good 15 minutes before heading out. I noticed that when I put the car in reverse the lights would dim and the fan speed would decrease yet the battery voltage stayed the same (Or at least thats what it was telling me). This happened for a week straight and I finaly went and got a nice sears 1K CCA battery. But the problem is still there.

Im worried that the Alternator might be going bad but the battery voltage has never dropped below 13.8.

Any ideas?

Sorry for the slow response. Been on vacation and also moved so havent had internet.

Everything in the car checks out. Autozone ran their diagnostics and found the alternator to be charging just fine.

Weird. I also noticed somthing else weird which I will be making a new topic about.

I've been having the same issue with my 2004 GT1. Pulled the alternator and had it tested and it was fine, although I had the brushes replaced, due to whining. Apparently the 2004 has a special expensive alternator, don't know why but on all the gm-parts sites I've checked its more expensive compared to 2003 (same dimensions) but 215 amps vice 205, and 2005-2006 that I've been told won't work in an 04' don't know why. I then replaced the 5 year old AC Delco battery-went with a diehard gold. Same problem, took it to the local dealer and its not throwing a hard code, problem is intermittent.
I've checked the cables and replaced the belt when I did the alternator. The belt tensioner seems fine, but didn't request the dealer to check it.

At a loss, eventually I'll be on the side of the road and then I'll know what's what