"I have the battery light come on in my truck....voltage is good...on the gauge...and even when i put my voltmeter on the battery....Do I have a charging issue as well..or just a wonky light? If I step on the gas...the battery light turns off....but no difference on the voltmeter...always a good charge...so I haven't worried about it.

Any Ideas for my situation "



First thing, you might want to check your terminals, etc., and make sure they are all ok - clean, not frayed or burned, etc. I recently took mine off and cleaned em up real good with a wire brush and it helped with my issue.

Definitely a good idea to test your alternator. If its a little weak, it might be charging good enough while you are driving around (at higher RPMs), but not at idle. And, if its getting a litte weak, it could blow your batteries.

I've had some batteries do wierd things in the past, like having trouble charging at lower alternator output voltages, but then usually testing OK with a voltmeter.

If you can get to a parts store that can bench test the alternator and batteries, that's probly the best way to do it. Have them run the alternator a couple times in case there's an intermittant problem.

If you can't get to the parts store, the basic testing method for batts and alternator is to test voltage at idle, then raise the RPMs, and the voltage should go up a certain amount depending on your system. If you don't have the testing procedures and specs, I probly have em somewhere - let me know.

Also, the voltage regulator on these trucks can do weird stuff, including messing up the readings on the guages and stuff. I don't know the testing procedure for the regulator, but I'm gonna check around and see how to do it. I'll let you know.

 

96, I have the answer to your question. My 96 had the same exact problem. I mean EXACTY! I tested the alternator, it was good. Changed the voltage regulator because I had a spare. And it still did it.

It's the white wire in the 3 wire clip. This is how I fixed it.

Pull battery cables.
Pull the 3 wire connector off.

Inside that connector is a plastic red lock. Use a pic to pop it out. Then your wires will come out the back. Clean those connections and crimp them just a little bit to help them make better connections. Put the wires back in and install the red lock. I knew it was those wires because I finally got out under the hood at night and wiggled them with the lights on. Of course the lights went crazy. Every since I cleaned and tightened those connector pins It's been smooth sailing. And try to help the single wire connector while you are there. That should eliminate your problem. But you are right, you alt is charging, the idiot light is having connection problems. Good luck man.

RubberDuck

 

cool...a fix that won't cost me an arm and a leg....everything tested ok....but I was at a loss to figure this one out....will deal with the wires...when it warms up...it's freakin cold up here this week.

Yukonsly

 

if that does not work(I hope it does),check your output lead for an ac voltage leak. You may have 1 diode not rectifing the voltage 100%. just checking for voltage at the battery does not always isolate your problem. if this happens to be the case, you may start to see your unit operate poorly due to noisey power supply to the PCM. good luck.