98 Valeo Alternator 110 Amp.
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Instructor
Joined: Sep 2017
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98 Valeo Alternator 110 Amp.
My volts are dropping so I disconnected the positive cable while running, with a multimeter while running it was putting out 12.2 to 12.3 volts. I know it is a valeo. It's on a 98 C5. What should I do because I know the Valeo brand is expensive from the dealership and I dont believe a aftermarket brand will work from what I read on the forum. The battery is good I put a optima red top in a few months ago.
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From: Washington Township Michigan
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You don't have a solid location listed in your profile other than USA, so I suggest to find a local, reputable facility to you which can rebuild the original. Critical item is to use Valeo regulator too.
I have a fairly new AC Delco GM Reman, which was on my C5 when I bought it and had the dreaded Charging System Fault pop on occasionally, found an original, rebuilt it, and then purchased a Valeo regulator for the AC Delco and it functions as well as the original Valeo 110 amp.
The "remans" will function fine as long as the regulator is correct.
I have a fairly new AC Delco GM Reman, which was on my C5 when I bought it and had the dreaded Charging System Fault pop on occasionally, found an original, rebuilt it, and then purchased a Valeo regulator for the AC Delco and it functions as well as the original Valeo 110 amp.
The "remans" will function fine as long as the regulator is correct.
Melting Slicks
Joined: Jan 2009
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From: Miami FL
Take a look at this post for an in-depth analysis of the C5 alternator.
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.
For a potential 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.
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Joined: Apr 2007
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From: South Western Ontario
I'd clean the main battery connection at the solenoid first. Lots of poor charging caused by that connection.
GCG is the man when it comes to listing all the required info for these alternators. If you think you need more current, get any higher current alternator which uses the same physical requlator mounting and install the correct one he linked to
As noted above, never disconnect the battery with the engine running..
GCG is the man when it comes to listing all the required info for these alternators. If you think you need more current, get any higher current alternator which uses the same physical requlator mounting and install the correct one he linked to
As noted above, never disconnect the battery with the engine running..
