Service Charging System
 

I am getting the "Service Charging System" message on the DIC. When this happens I notice that my voltmeter is dropping.

This only happens when my fans kick on and only at idle or very low speeds.

The voltage drops to about 13 when the low speed fan kicks on and drops sometimes below 12 when the high speed fan kicks on.

I'm guessing a bad alternator. Any other ideas?

Possible, but your battery could be on its last legs. The extra juice for the fans could be just enough if the battery is failing. Does it do it when you turn on lights?

Lots of variables here, age of battery and driving habits are big ones. If you only drive occasionally or only take short trips your battery may be low.

Chevy batteries are shit to begin with. I put a tender on any time my 07 is to sit for more than a couple days. I got rid of my 05 because of impossible (at that time) to find battery problems

The battery is fairly new. 8 months old probably?

No, it doesn't do it when I turn on the lights.

It is my daily driver.

Being it’s your DD, unless your drive time each way is more than 15 miles or so the battery does not get recharged enough to compensate for the start power and juice used for other purposes( Ac, lights, on-star, sound system/nav ETC)

If more driving than above it could be your alternator as you said or perhaps something is staying awake and leaching current. Lots of fancy computer controlled circuits and some of them might not time out after the car is shut down!

Sounds like it is time to see a Pro

Good luck. Dave

Yeah, my daily commute is about 20 miles or so each way and the original battery lasted about 3 years so I don't think that's it.

I hear you can go by Pep Boys Auto and they will check the alternator so I think that will be my next step.

Thanks for your help Dave.

David :cheers: