Battery light on and engine pulsates. The lights dim then brighten.

What is your question?

Replaced the alternator and had battery checked. All was good. Cleaned all the grounds. Checked all the fuses. Traced the ground cable all connections were good. Replaced the PCM and still have this problem. Any other ideas?

Andrew32 in Munroe Falls OH

Jul 13, 2015

1 Reply

Popular Answer

stevieray1on Jul 13, 2015

have the NEW alternator,and the battery TESTED again.maybe BAD(NEW)alternator right out of the box!seen many times!

Andrew32on Jul 13, 2015

I had both battery and alternator tested. The alternator was tested on and off the car. It check's out fine. Could it still be bad even know it checks out good from the test stand and on the car?

stevieray1on Jul 13, 2015

do you have a volt meter?

Andrew32on Jul 13, 2015

Yes I do have one

stevieray1on Jul 13, 2015

check the battery voltage(DC)volts with the car off.then check it again with the car running.post results.

Andrew32on Jul 14, 2015

With the car not running 12.63V With the car running it jumps around the highest point is 14.79V and the lowest point goes to 13.98V. With the car running I removed the positive cable from the battery and the car was still running and still was pulsates. The I removed the neg. cable the car still ran but the pulsating was much more and all the lights in the dash were blinking, then it stalled out. Then I put the cables back on and still doing the same thing with the battery light on and engine pulsating.

stevieray1on Jul 14, 2015

well the voltage test you did is good.BUT,you just may have really FRIED something from pulling those cables off with the car running!!YOU CAN'T DO THAT!AND DON'T DO THAT!.I hope the computer is ok?what you did was old school,you could do that in 1975 to check and see if the car cut off,but never do that on these modern day vehicles!

Andrew32on Jul 14, 2015

I guess I am at my wits ends with the car. Everything is still the same. I do have another PCM module but that is not the problem. Another alternator is $160 bucks and if its not the fix I can not return it. Do you have any other ideas what it could be?

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