My son has a 97 V6 5spd. Recently, as he accelerates out of a stop, the "Battery" light has started to come on as he gets to about 2200-2500 RPM. After he upshifts, and the revs drop, the light goes off, until it reaches the next shift point at 2200-2500.

Anybody know why that might happen? My first thought was the battery, but he has no trouble starting it, the battery seems to have plenty of charge. Maybe the alternator is failing under load and drawing power from the battery?

Any advice would be appreciated.

 

sounds like the regulator has gone. So when the engine revs, the alternator is outputting too much juice.

Get an voltmeter across the battery terminals when the engine is running, that'll tell you if my deduction is correct!

Good luck

 

thanks Muzzy, I 'll pass it on to my boy--He's 400 Miles (640 km) away at college--hopefully he will have sense enough to check out your tip