ABS, TCS off, service light, fuel and temperature gauge fluctuation

KEITHBAILEY85

MEMBER
2001 PONTIAC MONTANA
6 CYL
2WD
AUTOMATIC
156,000 MILES

Okay, so I was driving to get some food on lunch break from work and it started fine was running like usual and out of nowhere the battery light started flashing but nothing happened. Then on my way back to work it came on again and my lights dimmed and the blowing of heat slowed down. After about two minutes it went off and everything was fine again. It did this off and on like four times. So then after I got off work I started it and the light was on and stayed on but was still running okay until I was about halfway home and then all my gauges stopped working, low fuel light came on, air bag light came on, lights got very dim and it was driving as if I came to a complete stop that it would shut off. Had some battery issues when I first bought it but I got a new battery n everything has been fine up until now. However, it has only been five months on a new battery. C305.

1 Reply

CARADIODOC

MECHANIC
33,752 POSTS

You have a charging system problem that is not charging the battery while you are driving. Once this becomes a permanent failure, at most, you will get about one hour before you are sitting on the side of the road, provided you do not use the heater fan or head lights.

Given the intermittent nature of the problem, it is likely due to worn brushes inside the generator, but this design is not practical to take apart to repair. Your mechanic can perform a load test to confirm the generator must be replaced, but any testing must be done while the problem is occurring.

Be aware that this generator was redesigned for the 1987 model year and has an extremely high failure rate. I can provide more detail if you want me to, but to reduce the real high repeat failure rate, the battery must be replaced at the same time unless it is less than about two years old. You have a new one already, so you do not have to worry about that.

Do not worry about the multiple warning lights. Those are due to those computers shutting down. They know they cannot do all the things they need to do when system voltage is low. They will go back to working normally once the charging system is working.