C6 Electrical Problem

[Greg J]

I own a 2008 C6 Corvette with slightly more than 53,000 miles. I love the car and it has been mostly problem free for the past 7 years. Three months ago the generator/alternator failed (it flatlined). I replaced the alternator and everything worked fine for about one month. Then suddenly the volt meter (on the dash) started to show the system over charging. The normal reading was 14.5 volts but it started to show 18 volts or more. I checked the battery with a meter and it was registering 19.89 votes. After having this happen three or four times I concluded the voltage regulator in the alternator was failing and I replace the alternator for a second time (FYI, I ran the engine for less than 30 seconds each time it was overcharging). I have just finished the repair. I turned the car on and everything worked fine (volt meter showing 14.5). After running the engine for several minutes I turned it off and restarted the car and the volt meter on the dash read at +/-18 volts. I turned the car on and off several more times and it jumped from 14.5 to 18 volts. Does anyone have an idea on what is wrong?

[m and t's77]

Where are you getting your rebuilts?

[Greg J]

I didn't get a rebuild. I purchased a new AC Delco alternator from Rockauto.

[wwomanC6]

I'm having electrical problems but something keeps draining my battery. Two previous batteries lasted almost a year before drained. The last one I just put in 3 weeks ago. Drove it once after changing. Started the car two weeks ago. Yesterday it was reading 0.0 volts.

[Sneaks]

I'd start by pulling fuses and see which ones are pulling current with the ignition off Wendy.

[Bucwheat]

Wendy do you have a radar detector hard wired on your car?

[wwomanC6]

No. But in the service manuals I found a note in the procedure to find an electrical drain about the OnStar System, which I do have.

[vetfever]

My car is on a battery tender while it sits in the garage between outings. Too many electrical things going on with these cars that will drain a battery if the car is not driven often enough.

[Datawiz]

The terminal in your starter, fused in the plastic, is likely falling out, causing a short. Plastic housing it rots over time due to heat.