The car had battery light on for 2 days before it can't start. after replacing the alternator, runs fine. But the battery light will occasionally turn on for a few second and then turn off(starts to see the light after the car run sfor a few miles). The battery was bought from costco 1 or 2 years ago. Mechanics says after replacing the battery, the light will not turn on. So it's battery problem? How to be sure it's battery problem? I need to ask costco for their warranty.

 

That is not the battery light, it is the charging light. A bad battery will almost never turn that light on, only a bad alternator. If you bought a parts store brand alternator, especially an Autozone it's likely the alternator is bad. Get a name brand alternator, the best is Denso, but I've had good results with Pure Energy products. You can get it at Rockauto, you pay for the core, when you install the new one, go back to rockauto website and click on return and purchase a return shipping label from rockauto for cheap. Put the old one back in the box and drop it off at Fedex. You will get the core back, minus the shipping label in a few days.

https://www.rockauto.com/en/catalog/...generator,2412

 

I agree with what the guy above me said. The alternator is the issue. My wife has a 2006 honda civic in which we changed the alternator out because of bad diodes. We bought a reman alternator from autozone and the battery light kept flickering and we were having issues with charging the battery. I thought it was the battery, so we had it checked out from two different sources; both said battery was great. We replaced the new reman autozone alternator with another reman one and the problem went away. This was last year november and the car still runs great.

 

great advice, Im like sufferning here. Hubby bought me a new battery last one was leaking, and same thing with the light and the car doesnt turn on. Only with a boost and then dies. great info. very much needed. have a good day

 

my car is doing the same, except the headlights and ac are flickering with the battery light