Alt light?

I have driven the Comet very little since last year. I moved it over to the garage at the new house, and the alt. light is staying on. It starts fine, runs fine, lights are fine, but the alt. light won't go out. Nothing has changed since last year.

What makes the alt. light come on? Failure to charge? Lower charging rate?
Bad battery?

I haven't had the alt. checked yet, connections are not corroded anywhere,
everything is tight.

Seth

 

Fastest way to check if your charging is start the car and disconnect the positive cable while the motor is running. If the motor dies your not charging.

I just bought my car 3 weeks ago or so and my system wasnt charging, turns out the wire fried from the BAT on the alt to the battery. My light didnt work at all

Oh forgot to answer the question, it works off of voltage, which comes from the voltage regulator. It has 4 pins with letters A-S-F-I. which I believe stands for Armature, Stator, Field, Idiot . The I is what controls the light

Ben

 

I'll try that.

I really didn't want to pull the alt. without trying other things.

Seth

 

Seth, one thing to check is the belt. A loose belt can make the light come on. If you can turn the alternator fan by hand, it is too loose. Quick and simple to check. Could also be the regulator. Another easy test on the regulator would be to take the one off your other car and plug it in, making sure to ground it and see if the light goes out. If that isn't it, my guess is going to be a bad diode in the alternator.
Taking a battery cable loose will tell you sometimes if the alt is bad but not always. An alt only has to charge a little to keep the engine running so it can be working at 20% capacity, keep the engine going, and still be bad. If the light stays on after you test the belt and regulator, might as well take the alt off and go get it checked at your local parts store.

 

By the way if you dont have another voltage regulator to test, you can bypass it by pulling the wire plug out of it and jump locations "A" to "F", if it starts charging then the voltage regulator is bad.

 

I'll try that.

Thanks to all. She may have heard me talking about that '69.5!
She could be a jealous old girl.


Seth

 

Quick Fix .... :evilsmile

 

?

What am I going to do with that, cover the 'ALT' light?

 

Like he said..."Quick Fix".

 

You might try jumping a wire from the big post on your alt. to the battery. If the motor boggs down like you just turned the air cond. on then the Alt is working fine. Chances are you have a short in the dash.
Just a thought.
Happy MAV/Cometing
Jerry Fow 2