blowing alternators
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1st Gear
Joined: Oct 2018
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blowing alternators
I have a 2002 z06 and it has less than 10,000 miles. the alternator is not charging and tests bad. The shop tried putting in 2 different new alternators and they both in minuets. They told me to take it some where else. What should I check ?
1/4 mile/AutoX
Joined: Jun 2014
Posts: 11,440
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From: Buffalo Texas
you can't just replace a C 5 alt, should have rebuilt yours ?????
https://www.corvetteforum.com/forums...nd-issues.html
https://www.corvetteforum.com/forums...nd-issues.html
Melting Slicks
Joined: Jan 2009
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From: Miami FL
As mentioned above, read it and DON'T turn in your old alternator as core: plenty of horror stories!What makes this alternator so peculiar is that it is excited when its regulator receives a turn on signal of 10v at limited current provided by the PCM through the L wire. Not all regulators accept the turn on signal provided by the C5 PCM.
Another distinctive attribute described by Lionelhutz in this post:
The stock alternator has a soft turn-on regulator. You can watch how slowly the voltage increases when the engine starts. So, I suspect the message is caused by some aftermarket units that do not have a soft-start and basically jump to a high duty cycle until the voltage rises and the duty cycle drops again. The PCM is seeing the duty cycle go too high which triggers the charge fault message in the DIC.
If you are going to take the rebuilt route, take a look at this post. It has info on the right regulators for both, 97-01 and 02-04. The price is around $30.
This other post has detailed info on the rebuild procedure and links to get the other parts.
Last edited by GCG; Oct 24, 2018 at 08:20 PM.
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Why do you think you need a new alternator. What is it not doing?
The alternator charging wire connects to the starter solenoid and then goes up to the battery. Check the main terminal on the starter solenoid to make sure that its clean and tight!
It could just need new brushes. Its a very simple repair that you can undertake. OR, you can have yours rebuilt! That's the best route.
There is a very good You Tube video on what goes wrong with our alternators and how you can just replace the brushes if they are worn. Just search you tube: VALEO ALTERNATOR REPAIR, COMMON PROBLEM BRUSH CHANGE for a very good repair procedure.
If the regulator is bad, you can replace that also. Just have to get the correct regulator.
The alternator charging wire connects to the starter solenoid and then goes up to the battery. Check the main terminal on the starter solenoid to make sure that its clean and tight!
It could just need new brushes. Its a very simple repair that you can undertake. OR, you can have yours rebuilt! That's the best route.
There is a very good You Tube video on what goes wrong with our alternators and how you can just replace the brushes if they are worn. Just search you tube: VALEO ALTERNATOR REPAIR, COMMON PROBLEM BRUSH CHANGE for a very good repair procedure.
If the regulator is bad, you can replace that also. Just have to get the correct regulator.
