My battery lights on and lights flicker

joew623

Registered User
OK, Im driving along and my battery light comes on...so i drive to auto zone to have them test my duralast alternator i bought from them last year. They put the machine on it and tell me to hold the RPMs at 2000 and the machine says its putting out good voltage/current. He said the alternator was fine. next he checked my battery and it said it was fine. but the light is still on. it comes and goes. sometimes it blinks on and off quickly, sometimes it blinks slowly, sometimes its on for 5 minues straight. now, my girlfriend was looking at directions with the map lights on, and i noticed that the dome lights flicker and dim/brighten as the battery light goes on and off. the car always starts, and doesnt ever go "dead". What could be causing this? Im thinking maybe some sort of voltage regulator is going crazy but have no idea. Thanks
 
You're not nuts, but you are a bit screwed.... Your Duralast alternator is about to stick it to you. Its on the way out and specifically, its the regulator part which is going. You will probably see this happen more and more frequently and the problem will vary with engine idle. For example, when you first start the car, things will be fine, then as you drive the light will come on and go out. If you had a volt meter connected up (for example to the cigarette lighter), you would see the alternator drop out and the battery take over. It would read 12V and slowly but steadily drop.

What you need to do is to keep the battery charged up at night with a charger and keep a cell phone and some jumper cables handy; you will probaly get stranded somewhere and need help. A tip on jumping the car, hook up the cables and let the booster car charge up your battery for 10-15 minutes before you try to start it; no need to REV the heck out of the booster car (thats just displays ignorance), 1000-1500 rpm is fine. You are trying to build up some reserve and that won't happen if you yank the charge off the battery by cranking the engine right away. The longer you can let it charge up, the better.

Once your alt finally dies, then you can take it back to Azone and they might trade it out. I went through the same thing.
 
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