Hey Guys and Ladies I'm trying to fix the "Service Charging System" on my 2011 Grand Sport and I'm looking for helpful advice from those who have experience this issue and found the fix for it. My car (Red Lucy) is a 2011 Grand Sport A6 with a Procharger D1SC, 60lb inj, Boost-a-pump, LT Headers w/ X pipe, BTR stage 2 Cam, NKG spark plug, stock AC Delco plug wires, and stock pulleys.
Sooooo what happen was.. Back in Aug I got the Service Charging System message in the DIC. I looked at the voltage gauge and it was below 11 volts. So I made a quick u turn and headed back home since I was only 5 minutes out. Later on I took the alternator off and took it to get tested and it failed. So I brought a new (reman 140 amp) alternator from O'reilly's. I replaced the battery about 5 months prior so the battery wasn't an issue all I had to do was charge it. I installed the new alternator and took Lucy out for a test drive. Initially everything seems to be all good until I notice after about 10 minutes of driving I notice when I'm stopped a traffic light the voltage go from 14+ to 13 to12 and as low as 11.8 if it's a long traffic light. So I took that alternator back to the auto part store for a replacement. After the second alternator install I got the same result, so I decided to check the cable connections at the starter. The connections at the starter was loose because of heat damage so I replaced the starter/solenoid and covered it with a heat shield. So now at this point I have a fully charged battery, new alternator, new battery terminals, tight cable connection with no corrosion, and no blown fuse. I even re-routed the cable coming from the alternator going to the starter away from the #1 plug wire and I’m still getting the Service Charging System message when the voltage display is showing 14.1 in the DIC. The voltage hovers around 14.1 while driving, but when stopped at a traffic the voltage will drop to 13.5 -13.0 and 12.5 – 12.0 if it’s a long light. I’ve read a bunch of threads on this issue and most of them were caused by installed under drive pulleys and I’ve even read using NGK plugs and non ac delco plug wires on a stock engine will cause interference in the charging system that will set off the service charging system in the DIC. I am frustrated at this point. Has anyone delt with this and found the fix?

 

For a start, beyond the "Service Charging System" message, what codes are you getting?

 

Try some LS9 factory plugs gapped at .028

 

Have you checked the main grounding point for the charging system? Remove, clean and put dielectric grease

 

Below is a link to an older topic related to alternators………………….. worth looking through and reading, especially Dano's comments

https://www.corvetteforum.com/forums...or-advice.html

 

Your NGK plugs are likely the issue. If you are running them because you are boosted, replace them with LS9 plugs. AC Delco 41-104.

 

https://www.corvetteforum.com/forums...stem-mssg.html
Sometimes search actually does work....

 

There are no codes in reference to the Service Charging System.

 

You're right the search function does work. I've used it many times to find info to resolve or fix issues I've had. Thank for you helpful link.

 

Take that Oriely's back for a refund. Trust me on this.

No matter what they say their alternators do not work in Vettes. Find a re-builder in your area. I went through 3 from them with them guaranteeing that it would work. Finally told them to shove it some where and refund me. Found a local re-builder and problem solved.

the 3 I had from them did the following
service charging system
overcharging alert
or caused the volt gauge to flop around like a see-saw.

Had my old one rebuilt with Valeo parts and all issues gone.

 

Thanks Bravo29! You are 100% correct Oreilly's reman alternators are garbage!
I brought and installed a Mechman alternator and problem solved. I no longer get the "Service Charging System" message in the DIC.. The voltage holds at 14.8 on startup. At engine operating temp the voltage holds at 13.5 - 13.8 with the car idling in gear (10 minutes), and the AC on, dual Spal fans running, headlights on, and AC fan on high. With the car idling in park without the Spal running the voltage holds at 14.0.

 

A oem Delco alternator for a 2010 Ls3 Vette would produce how many amps? Thanks