C5 dead battery question

[Brian J.]

A couple of days ago I tried to start my 99 and the battery was completely dead. I didn't have time to put a charger on it, so I just left it be. I noticed a high pitched tone comming from the car, after I tried to start it. I could hear it for days, just barely noticeable. Does anyone know what this is?
Also when I put a charger on it the amperage reading kept fluctuating (pulsing) for about 20 mins (on the charger). When I started the car it was fine. Does anyone know what the high pitched tone is, and what the pulsing amp gauge is?
Thanks for all the help in the past,
Brian

[Larry Parylla #41143]

Re: C5 dead battery question

C5s are known for their habit of killing batteries. Keep a battery tender on it at all times and watch the battery for any signs of leaking. The battery is right above wires and vacuum lines, and there is a chance that and acid that leaks can damage the computer.

[Warren F.]

Re: C5 dead battery question

Brian:

Had that happen to me as well. Didn't drive the '02 for a month and half. Put a charger on while battery is hooked up and got the same pulsing, the noise I heard sounded like the electric fuel pump working on my car. I unhooked the battery while charging a short while, just to get it started. Went to the dealer told them I thought I had a defective battery. They replied; has it been a month since you drove it, if so there is enough electronics on board to drain the battery, they said that GM figures there is enough battery to start the car if it is left at an airport parking lot for a month. This news was kind of an eye opener for me, now I just make sure it's driven every couple of days!

[Brian J.]

Re: C5 dead battery question

The battery is not the original, this sounds kinda strange since the car is only 5 yrs old and already had 2 batts. I failed to mention the car stays outside here in CT that is probably a factor. Nothing like my 66 no battery problems,simpler is always better.
Brian

[Warren F.]

Re: C5 dead battery question

Brian:

Same with my '71, simpler is often better.

[Larry Parylla #41143]

Re: C5 dead battery question

I bought my 98 in March of 98, I went though 4 batteries from 1998 to 2001. When I put in the 4th battery I started using the battery tender. After the battery tender the 4th battery lasted from 2001 till last summer. My 96 is hard on batteries also but not anywhere near as bad as the 98 was.