96 Silverado draining battery

I have a 96 Silverado, 2WD, 5.7, auto, ext cab with 230,000 miles on it. It has suddenly drained the new battery (installed in October) twice during the last 4 weeks while sitting. I do not use it much in winter but try to run it once a week. The weather has been nasty though and was not able to drive it for 2 weeks, battery dead, NOTHING. I slow charged for a day until voltage was proper. Wrote it off as maybe just the door not closed etc. but found it dead AGAIN 4 days later. I have not been able to do circuit testing but pretty sure I found the culprit. The ceiling light turned on by itself while I was charging again and doors were closed. After manually turning it off it has not repeated itself so far. Normally I leave it in the on position and it turns itself off, just as my 04 Blazer does. is this an easy fix or am I better off just leaving the light off? I do not have a manual for this truck as of yet, but sounds like a relay possibly a problem. Anyone deal with this before?

I have a 96 Silverado, 2WD, 5.7, auto, ext cab with 230,000 miles on it. It has suddenly drained the new battery (installed in October) twice during the last 4 weeks while sitting. I do not use it much in winter but try to run it once a week. The weather has been nasty though and was not able to drive it for 2 weeks, battery dead, NOTHING. I slow charged for a day until voltage was proper. Wrote it off as maybe just the door not closed etc. but found it dead AGAIN 4 days later. I have not been able to do circuit testing but pretty sure I found the culprit. The ceiling light turned on by itself while I was charging again and doors were closed. After manually turning it off it has not repeated itself so far. Normally I leave it in the on position and it turns itself off, just as my 04 Blazer does. is this an easy fix or am I better off just leaving the light off? I do not have a manual for this truck as of yet, but sounds like a relay possibly a problem. Anyone deal with this before?

the door switches are suspect..work them manually see if the all work the same/tension etc..most likely driver door switch.

Thanks, will check that out!

Is it possible running the truck for a decent amount of time with a bad alternator too?

No, the alternator is fine. The problem is that since I do not drive it everyday it will simply drain the new battery while sitting. Even with an 8 hour charge and no driving it did this. So far after disabling the dome light it has held up fine. Seems like this is a common problem after I started to read older posts. Some people have bad door switches, some were having other possible issues. The lights at supposed to turn themselves off normally after shutting the door but will randomly turn back on again or not turn off. Apart from the door switch I would guess maybe the timer mechanism could be a problem, but unsure what that is at this time. But most people seem to have cured the problem with a switch, as suggested.

disconnect the neg. term on the battery and use a test light to connect the neg. lead to the batt. term. If the test light lights up then you have a draw on the battery. Leave test light connected and start pulling fuses one at a time. When the test light goes out this will let you no where the draw is coming from. Reinstall suspected fuse and start unpluging things on that fuse circuit untill test light goes out and that is your problem.

disconnect the neg. term on the battery and use a test light to connect the neg. lead to the batt. term. If the test light lights up then you have a draw on the battery. Leave test light connected and start pulling fuses one at a time. When the test light goes out this will let you no where the draw is coming from. Reinstall suspected fuse and start unpluging things on that fuse circuit untill test light goes out and that is your problem.


read his inital posting he found." when charging the dead battery the interior DOME LT. came on by itself "

Thanks autotech, that is good advice but so far looks like my problem is the light coming on randomly. To tell you the truth, with the lousy weather we have had for the last 2 weeks I have not been able to do anything with water freezing up and snow and ice causing me grief. The battery still starts the truck with the dome light overide set to off so that MAY be it, but I read a post where another person had the same thing happen with the switch set this way too. I will run this test if I still have problems.