A couple weeks ago (after getting dealership work done on an unrelated issue) I got a service charging system warning and my battery voltage fell from ~14.4 to ~11.8... I kept the rpms up a little more than usual and it jumped back up to 14's. Turned off the warning and it was fine. I got the same message last week and did the same thing. Now sometimes when I try to start the car I just get a loud dead click with a check engine light until I release the clutch. (The battery also reads ~11.8-12.5 when turned off), I have to try and start the car over 10 times before it will actually start, and when it does it starts up beautifully and perfectly normal, and the battery jumps back up to ~14.5. What is going on?

 

the voltage you are seeing when the car is running is not the battery voltage - the voltage that you are getting with the car off is within the normal range - I have found that it will start as long as the voltage is north of 11.6

 

Dealer may have let the battery drain while they were working on it. If the battery is old it may have not been able to recharge . Get it tested.

 

Also:

-- Check the battery terminals. Are the clamps tight? Any corrosion?

-- Crawl underneath and check for corrosion/damage at the starter solenoid.

More ideas:
http://forums.corvetteforum.com/c6-c...t-problem.html
http://www.ls2.com/forums/showthread.php?t=846931