Generator light
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Joined: Sep 2007
Posts: 55
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From: Buffalo NY
Generator light
Ok, my generator light goes on very dim (hard to notice during day light).
The strange thing is, when I pull the emergency brake handle up, the light goes off and the amp meter shows a slight increase. A few seconds go by and I need to do it again. Alternator has been replaced(Thinking that was the problem) but it still continues. Battery seems good, I have no starting issues or battery discharge over long periods. I'm thinking weak ground associated with the break lights, But they all work!
Any other ideas?
Thanks Carl
The strange thing is, when I pull the emergency brake handle up, the light goes off and the amp meter shows a slight increase. A few seconds go by and I need to do it again. Alternator has been replaced(Thinking that was the problem) but it still continues. Battery seems good, I have no starting issues or battery discharge over long periods. I'm thinking weak ground associated with the break lights, But they all work!
Any other ideas?
Thanks Carl
Instructor
Joined: Sep 2009
Posts: 135
Likes: 2
From: Waterbury CT.
Carl your generator light works off of opposing voltages. With the key on and engine off power goes through the bulb and goes to ground in the generator. When the engine starts, the generator charges and the control circut (voltage regulator) in the generator now removes the grounding and puts power out on that circut. With equal voltage opposing on both sides of the bulb it then goes out. From my twenty one years of being a GM dealer tech; I've seen this many times and it has ALWAYS been the diode trio in the generator. Very common on rebuilt alternators. Remember "NEW" means your the first person to use it. It doesn't mean it's good. Open up the generator and check the diode trio. One of the three diode legs is open and allows small amounts of current to flow both ways. This will give you a very dim light.
Steve
Steve
Melting Slicks
Joined: Apr 2008
Posts: 2,628
Likes: 243
From: Russell Ontario
St. Jude Donor '09
Steve is bang on on this one , if you want help to re-build your alternator I wrote a small article on our clubs website, Capital Corvette Club, in Ottawa , just look under Ron's tidbits!
