Electrical Drain

[Skyguy007]

Lately Iv'e been encountering a low battery situation with my Grand Sport. The first sign of trouble when the key fob doesn't unlock the doors or turn on the interior lights as I approach the car. Until a week ago, there was one of those cheap quick disconnect devices on the battery, which I removed. I thought the problem was fixed since the power was restored immediately.

I have a small battery booster that fires the car right up when I hook it up to the car battery. The volt reading on the dash varies from 13.8 up to 14.3 once the car is started.

The car has a fairly new battery, which I will have checked in the next few days. But I'd like to know if there's something in the Vette that might stay "on" when the car is just sitting. I read somewhere that the alarm goes into a "sleep" mode if left alone for a while. I've checked the underhood lights, and they're turning off as I close the hood.

Any suggestions?

 

[Tonylong]

I had a similar mysterious drain problem on my '89. I blamed the "Battery Tender", the aftermarket alarm system, and evil spirits. I accidently found it was the door's
courtesy light switch. The courtesy lights would occasionely come on without my
noticing it since I always turn the alarm off as I approach the car. Try disconnecting
the switch at driver's door first. It easily unscrews and you can pull off the connector.
See if the problem disappears then. New switches are available from MAD for $10.
HTH LOL

 

[RedRagTop]

There are several threads on this subject you can read by accessing the search option at the top of page but suffice it to say that these cars do have a parasitic drain on them and lots of us have changed batteries and resorted to the use of tenders and such for longer down times. Is your battery original?

 

[Skyguy007]

The problem has been solved (I hope)! I removed the battery and discovered that the "universal" battery, which had both top and side terminals, had been shorting through the positive terminal on top to either the computer bracket or to some nearby wiring. The plastic cover on the positive terminal had almost melted due to the heat from the current flow and the battery showed about 3.5 volts! I'm lucky this didn't cause a fire.

I was able to find an open battery dealer who had a side-terminal only Delco battery for a C-5 on the morning of the 4th. So I cleaned out the battery tray, neutralized the acid residue of the positive cable, and installed a "correct" style of battery. It ran fine yesterday and just put about 350 miles on a road trip today.

I think I'll have a serious converation on Monday with the fellow who put the old battery in the Vette before I bought it. NO C-4 (at least not a '96) should have a battery with terminals on top, even if they're left covered.