I have a 2002 Lancer with only the battery light on. The brake light is not on. I had the alternator & battery checked at 3 different places and both checks good.

Any idea what would be causing just the battery light to be on ?

Thanks

Waid

 

wut. ..

 

Corrected. The battery light is on like this one!

 

At the battery with car off, my multi-meter reads 12.2V. With car on it reads, 15.5V. However, with my Android OBDII Scanner, it reads 14.4V.

Waid

 

i would trust a multimeter over a telephone for diagnosing electrical problems.

15.5 seems high, which points to a regulator issue.

12.2 seems low, which points to an old battery.

if it was reading low and "overcharging" to compensate, this would explain it all.


replace the battery.

 

Thanks Akzle,

I will put another good battery in the car and see if the light goes away. If not will replace the alternator and see.

Thanks

Waid

 

Found the problem! The Orange battery sense wire (Pin 2 on B-25) at the Alternator was broken but still attached to the alternator. I started from the Battery and traced it back to find where it was disconnected. Once I connected it, the light went away and all is well.

What is interesting is I went to 4 different auto parts stores with the Alternator and Battery and got 4 different answers as to what is bad. One AutoZone said the Alternator was bad and other one said it was good and both said the Battery was fine. O'Riley said Battery and Alternator was fine. CarQuest said Battery was bad and Alternator was good. So go figure!

Thanks

 

good job, happy ending and money for beer rather than replacement parts!

 

The Alternator for Lancer here is high $$$. I paid $25 for the used one but my Alternator is still good. I may just keep it as a back up just in case.

Waid

 

i put a new alt and bat on my montero sport and it srill dont charge dose anyone know why