i have a weird battery drain on a 2003 4wd blazer. takes a brand new battery from charged up to 3 volts in less than a week.

i have noticed that my gas, temp, and oil gauges come on after you shut any door and the interior light goes out. as soon as you open a door the gauges reset.

i have ruled out the alternator as i have done several load tests on it and the battery goes from 12 volts to 14.5 volts while running and drops a little when you turn every accessories to like 14.3 volts and rpm at 1500.

the visor lights have been removed both sides.

with seeing it was gauges i have blazer apart right now down the instrument cluster. i have found i have power at the orange wire going in with key out and the only other wire is a green one now with a 1.07 volts.

have battery out and waiting on it to full charger up to do a amp test.

any ideas would be greatly appreciated.

thank you

 

Good morning; I am going to describe what I have done in the past to locate battery drain. Many of the newer cars it does not work I have found. But I think it will on the Blazer. I disconnect the battery, either terminal. preferable the negative to avoid shorting. Connect a test light in series, clip one end to terminal to battery and the other to the battery lead. If you have a battery drain the test light will now light. On the Blazer you have two fuse panels. Start by pulling one fuse at a time and observe your test light. As I am doing this I replace the fuses so I don't have a pile sitting on the floor.When you find the right circuit that is draining your battery the light will go out. This will narrow your search. Hope this helpful to you


i have noticed that my gas, temp, and oil gauges come on after you shut any door and the interior light goes out. as soon as you open a door the gauges reset. When you say the gauges reset, are you saying they go back to normal? and the interior light goes out; On mine Blazer, I shut the door and lights stay on for a measured time than go out.

 

hi
with you question about the gauges. when i open the door they go down like they have been turned off. the interior light stays on for a few minutes and goes out then the gauges go up.
as for your test light i do not have one however have a clip on amp meter. so while watching the meter with the interior light on it is around 3 amps. as soon as the light goes out it drops to .2 -.27 amps. however you give it a few minutes it climps up to .8-.9 amps. i pulled the fuses.none make it drop except for the TBC fuse and it only drops (.2 -.27 amps) when i put it back in. leave it a few second then goes back up to .8 -.9 sometimes even to 1 amp. went to the BCM next when i pull the pink harness no change. pull the blue harness no change. go to pull the brown harness as soon as you touch the clip it drops. take the harness out and it drops to .01 amps. when i put this brown harness back in it spikes to almost 8 amps then now drops to 1.02 amps. now to look and see what is fed off this harness.

 

I am also a new member; but have been using the forum resources since I purchased my Blazer. I did find that you can scroll down on this post and you will find related posts below that might help you. I also found a link that talks about the BCM. https://blazerforum.com/forum/lighti...r-night-50970/
My problem was headlight switch, new one was not good had no dash lights. When you find your problem will be interested in knowing.
Larry

 

when i check the brown harness to see which wires have power. have power at A2 battery positive voltage, A7 RAP relay coil control, A8 interior lamp relay coil control, A9 horn relay control, A11 DRL relay control. when i checked this for voltage the battery was on charge at the time and all showed 13.7 volts.
tonight i have .2-.3 amp draw have pulled every fuse and does not drop below this. have not pulled any relay might have to pull a few of these relays.
i did find that the hazard switch was sort of broken and now is broken after i took it out. so ordering a new one and will have to go from there is i can get the amps to drop again.
i have found that the radio some times comes on by itself even after you have turned it off.

thank you for the replys. not sure how i missed that post. was worth the read. the amount that i have read of post this last weekend just so i didnot post something that has been explained every few months.

 

update.
seem the drain is gone. did change out the hazard switch.( i broke it taking it out. does look like it was going.) had took out the visor mirror lights. also fixed the ignition switch which sometimes you take the key out the battery light stayed on most of the times. also replaced the driver door switchfor the lights as it had been broken and i just unhooked it.
hook up battery and shut all doors wait 25 to 30 minutes and now no draw at all.
thank you for the help/tips Ebbervonfloyd.

 

That is great! My new headlight switch was bad and it was really great when my second one repaired the problem. Had purchased one on ebay and two on "Amazon. My problem started when I wanted to change out the burnt out lights in radio and heater control. I think I shorted out the first switch. Sure did a lot of reading. I have also purchased the GM Manuals off ebay. Found them to be hard to dig out the information.