The Alt and Diodes
Thread Starter
Burning Brakes
Joined: Jul 2005
Posts: 836
Likes: 89
From: Tucson Az
2017 C7 of Year Finalist
The Alt and Diodes
My Alt has been acting strange. It takes about a minute after starting the car to move over 13 Volts .I was talking to a guy today and he said he thought it was a bad Diode The Alt has to find another way around the bad Diode and that is why it takes awhile for the Alt to move up to 13 volts. Sounded strange to me but what do I know.
Ron
Ron
Drifting
Joined: May 2002
Posts: 1,607
Likes: 1
From: San Francisco CA
I have this problem from time to time. I've tried 3 different alternators and they haven't made a difference. I haven't been able to pin down what the problem is as everything checks out ok.
It might have something to do with the "generator sense circuit', which is the the wire connecting to the S terminal on the alternator. The service manual doesn't have much to say about it except that with the key on and the engine off it should be able to light a test lamp.
Mine doesn't regardless of how the alternator is behaving.
It might have something to do with the "generator sense circuit', which is the the wire connecting to the S terminal on the alternator. The service manual doesn't have much to say about it except that with the key on and the engine off it should be able to light a test lamp.
Mine doesn't regardless of how the alternator is behaving.
Le Mans Master
Joined: Nov 2005
Posts: 6,993
Likes: 25
Originally Posted by 50th year
My Alt has been acting strange. It takes about a minute after starting the car to move over 13 Volts .I was talking to a guy today and he said he thought it was a bad Diode The Alt has to find another way around the bad Diode and that is why it takes awhile for the Alt to move up to 13 volts. Sounded strange to me but what do I know.
Ron
Ron
Thread Starter
Burning Brakes
Joined: Jul 2005
Posts: 836
Likes: 89
From: Tucson Az
2017 C7 of Year Finalist
Thanks for the info. Didn't make since to me. I am only using the DIC so may it is off. I guess next week Iam off to the dealer. Just don't like that CHARGE SYSTEM FAULT and the Service engine soon light.
Ron
Ron
Pro
Joined: Dec 2001
Posts: 692
Likes: 0
From: antelope ca
do you have long tube headers ??? Check you connection at the starter ! If the battery connection is loose there you will show charging system fault .If long tube headers have been installed there is a thin wire that is connected on the large post at the starter solenoid that may be fried .I melted right through this wire after my flp header install .Good luck 
