twnturbz06

Hey guys, new to the site. I have an 02 C5 Z06 with an APS twin turbo kit. Car has been fine since I've owned it. Took it to the Dyno yesterday for a tune and started doing a couple pulls, we did about 4 pulls and it ran fine started the 5th pull and all of a sudden the Charge System Fault error came on and battery voltage started dropping. Put a new alternator and battery in the next day, took it for a drive and its still dropping to about 11 Volts until I shut her off. Was reading up on it and saw it could be the starter solenoid but wanted to get your advice first. Thanks for the help!

BigGun

You need to have the correct alternator in order for it to communicate with the pcm. This is a well known and common problem people run into when replacing alternators in the early C5. Your best and least expensive solution is to have your old one rebuilt.

NukeC5

The Duralast from Autozone works great and is really cheap

OP I chased this issue too. After a new bat and alternator it turned out to be the positive cable to the solonid had come loose. Check that the cable is tightened down. Also the battery terminals.

twnturbz06

Thanks for the help!

dadaroo

Here is the schematic for reference: