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Apr 1, 2009 | 04:37 PM

kyle37

Thread Starter

Heel & Toe

Joined: Apr 2009

Posts: 23

Likes: 0

Electrical

I am new to this and I'm not sure this is the right place for this.
I have an 89 Corvette and it appears that an electrical connection is draining the battery after the car is garaged for 8-10 day. I discovered the heater was in the "On" position after I charged the battery. I turned the heater off, recharged the battery and then disconnected it. Now the battery seems strong.
I thought the accessories were disabled when the engine was turned off.
Anyone have a similar problem?

Apr 1, 2009 | 06:19 PM

PONI ETR

Racer

Joined: Jun 2005

Posts: 481

Likes: 0

From: Lake Forest CA

I think yours is a C4. On the red tool bar, go to Forums/C4/General Discussion.
You should get plenty of help there.

Apr 1, 2009 | 08:11 PM

jfb

Team Owner

Joined: Mar 2001

Posts: 54,124

Likes: 30

From: Cincinnati, Oh USA

Accessories get their power from the ignition switch. First, in a dark place at night, check for underhood lights, vanity mirror lights, door map lights, center console light. Don't leave the key in the ignition because it keeps the anti-theft circuit on. Do you have a CB, GPS, radar detector, aftermarket radio, alarm, or audio amplifier? Check em.
You can locate the circuit discharging the battery by removing the neg battery cable and connecting an ammeter from the cable to the battery post. Switch the ammeter to lower full scale when the courtesy lights time out. GM says leakage current should not exceed 50 milliamps. My 87 draws 27 ma. and I have no problem. If you have high leakage, you can remove fuses one at a time while watching the ammeter to find the circuit at fault. Also, there are 8 wires on the bolt behind the battery. Remove the nut and remove the wires one at a time while watching the ammeter.

Apr 1, 2009 | 08:36 PM

pkazsr

Le Mans Master

Joined: Jul 2007

Posts: 5,356

Likes: 2

From: No HOA, New Hampshire

Cruise-In X Veteran

St. Jude Donor '09

Quote:

Originally Posted by kyle37

Yes yours is a C4, and the heater being in the "on" position will not kill a battery in a week. Now the fun begins. Just to get you started, connect your multimeter to read the current draw when the car is off. Should be about 5ma. If it is more keep it connected and start pulling fuses to find out which circuit is causing the drain. This is when the FSM comes in handy. Your 89 is more sophisticated than most other 89 Chevys and are a real challenge to trouble-shoot.
My advice is to read every thing you can about your Vette. If you plan on maintaining it, the Helms FSM is the first tool you need.
Mine is stored during the winter (down to -10* ) in a unheated shelter 5 months a year and I start it every 3 weeks, and it always starts.
This Forum taught me a lot, because I read first and asked specific questions later.
Good luck on finding your problem and if you could narrow it down I could send you a few pages of the FSM.