just got my brand new 125 amp alternator put in yesterday to accomidate my 1000 watt system and everything works fine except the battery light and "brake" light (the one that means your e-brake is up) periodically flash on for a moment and then sort of turn off but struggles to stay on, as if the lights are barely getting enough power or a wire is rubbing something very gently. it's really weird. all of the cables seem tight, i supposedly have a good battery, it's an optima yellow top and i had it load tested at autozone and they said it's fine. got any suggestions? i'd love to hear em!

thanks!

 

Get the alternator tested at Autozone as well. Double-check that all connections are tight on the alternator, and that the belt is well seated.

Intermittent stuff like that really is a pain to track down, though - could be as simple as a wire's insulation has rubbed through and from time to time it shorts against a body panel, or the internals of the alternator could be fscked.

 

Aftermarket alternator = junk.....

 

nah, you don't really think it's a bad alternator do you? it's brand new! the car seems to run better and the system doesn't dim the headlights nearly as bad, so i think the alternator's doing it's job. it's just the lights on the dash that periodically struggle to stay on... i don't get it! i checked all the connections, it seems that everything is tight. i tightened my positive connector on my battery just to be safe. it only started happening after i got the new alternator put in, so it has to be something to do with that whole thing. but why would the e-brake light come on too? doesn't that strike you as strange that out of all the lights to come up, the e-brake light and the battery light show up?

 

could it be that my new alternator is too powerful for the car? is there any such thing? could it be putting out too many volts? it's a really big, $300 alternator. it's puttin out 125 amps to power an optima yellowtop battery, a 1000 watt system, 2 one farad caps, and anything else i feel like powering (air conditioning, heat, headlights, xbox, tv, etc...)

 

The batt/brake light combo means a bad alt. Just because it's new (new, or rebuilt?) doesn't necessarily mean it's perfect.

 

I went through the same thing. My alt dies last week and I bought a AC Delco reman. 125amp and after a week the battery light would flicker. If you wiggle the connector at the alternator, the lights go off. I replaced the pigtail because the connector was worn out and loose going in to the alternator. The pigtail was $28.00 from the dealer. You might try that first.

 

brand new alternator especially rebuilds can be messed up formt he beginning......there is always a dud somewhere