bluesilver82

89 coupe 92,000 miles. I replaced the key ignition swithc assembly over thanksgiving because the car would not read the security pellet in the key. The wires were broken and mangled on the switch. I have not driven or started the car since replacing the switch. I went to start the car the other day and the battery was dead as a door nail. I jump the car and it started right up. I let the car run for about 2 hours to charge the battery. the car has sat for a week. I went to start the car again. The battery is dead as a door nail again. Jumped it and fired right up. Do I have a battery drain problem or is it just a bad battery that needs to be replaced????? I have no idea how old the battery is and it does not appear to be swollen.

AGENT 86

You can pull the battery and have it tested or pull the neg battery terminal and test for current draw, after courtesy lights have timed out.
One of those tests should help answer your question.

bluesilver82

thanks ill try the current draw method.

jfb

Measure the current, GM says it should not exceed 50 milliamps. My 87 draws 27 ma. and I have no problems. Don't leave your key in the ign as this keeps the antitheft circuit on. At night see if you can see the vaniity mirror lights on or the door map lights, the rear view map lights or the console light. Do you have a GPS, CB, radar detector, aftermarket alarm or radio or audio amplifier/s, check em.
Also, alternators aren't meant to charge up dead batteries, dead batteries draw large current at first and this heats up alternators and shortens their life. Besides, 2 hours of charging won't fully charge up a battery. Buy and use a battery charger and use it at least overnight.

bluesilver82

I will give it a shot. It held a charge overnight and I drove it to work this morning without issue. I may just take the battery and have it tested and buy a new battery and probably a charger too. I did not see any lights on and there are no aftermarket accessories that are installed or used in the car. Thanks again.

phat87

My battery in my 87 went dead acouple of times back to back. It turned out to be the under hood light had a faulty mercury switch an was draining the battery.

PS or BS FWIW, don't use your alternator to charge the battery, a charger is much cheaper than an alternator!

kenv

Every Corvette I have ever had would go dead in a couple of weeks of sitting. Now I use a battery tender on both of the ones I have now.

jtc44

All good tips but may I add? first I put in a code saver that way nothing has to time out then I put in a knife switch on the neg. side hook up my DMM then open up the switch and read the draw if I want to open the door I close the knife switch so meater does not draw to much amprage also start with 10 amp range just in case as you can see using the switch makes the changes easy IMHO

IAFF alumni

Yep. I put a BatteryMINDer on mine.