electrical drain

[kh440]

Here's a brain twister: Battery will drain overnight, did the test with a digital meter between neg cable and post, pulled every fuse one by one, with no dramatic drop in amp draw. (1.4-1.8), repeated test with alternator completely disconnected and same results. ECM unplugged and still no change. Charging system with vehicle running 14.27 volts. Fuse for lighter/clock has blown twice so unplugged lighter socket and taped up plug to prevent accidental arcing, and still no change whatsoever. And further complicating things: I don't remember having this problem until I had a new windshield installed: Don't see how one could have caused the other but I don't have a clue anymore

 

[BoostMasterK]

You are on the right track, but there are some fusable links and inline fuses in the car also. You best have the Buick manual to trace things out, but maybe this will help:

http://www.gnttype.org/techarea/electrical/wiring.html


From the high level Power Distribution schematic, I see the battery goes directly to the starter solenoid, but also through fusable links to the coolant fan, ignition switch, convenience center, horn relay, theft deterrent (through 2 inline 25A fuses which are taped to IP harness on RH side of the cluster), blower relay, headlight switch panel...maybe I missed some. Point is there's lots to happen before the fuse panel.

I'd start unplugging some top offenders from above like the coolant fan, theft deterrent fuses, blower relay, etc...

Hope that helps.


Mike [

 

[kh440]

You're actually the second person to mention fusible links. Something tells me these will be a bear to trace though..thanks

 

[equalizer442]

are you sure your dash board and hood lights are going off when you shut them, could be as simple as that.

 

[kh440]

99% sure about the lights, disconnected hood and trunk lamps, removed headlight and i/p dimmer switch. Meter reading never got below 1.42 amps.

 

[BoostMasterK]

Fusible link is just a fancy way of saying "wire that will burn up before the other wires"

Anyway, don't let that bother you....you will just be pulling connectors off parts downstream from the fusible links. In most cases, it's those parts (fan, relay, etc...) that are causing the slow drain anyway.

Consider yourself lucky it's not intermittent. You'll find it, just that you'll find it quicker with a schematic


Mike [

 

[kh440]

Thanks for the info and support, Should I start with the starter slenoid since i know where those links are, or does it really matter?

 

[BoostMasterK]

It could be anything, so I'd start with the ones that are easiest to get to first.

 

[salvageV6]

Go out and pull the fan delay relay as a test.

I'd also pull the ECM power connector apart and check that for draw.

The horn work okay?

Pull the connector off from the fans up front and see if the load clears.

 

[sam87]

don't forget circuit breakers

You didn't mention checking circuit breakers in the fuse panel so thought I would. I determined that my battery drain was thru the theft deterrent system, by checking for battery discharge with pwr accy circuit breaker removed.

 

[G McCall]

I had the same battery drain problem and found a few drains . The cars as their designed have a lot of drain anyway but I found excessive drain at (1) fan delay relay, and (2) Kirban "secret" cutoff switch. While these parts were causing problems I pegged my amp meter hooked up between the Pos. cable and battery Pos. post. With the two switches unhooked I still had like 4-5 amps (or is that mili amps), but it stopped my battery drain. I read and found that if a 12 volt test light will not light up when attached in line on the Pos. cable and battery pos. post your allright. With the two switches on my the test light lit up brightly, coincideing with the strong amp pull.

 

[BoostMasterK]

So, how does it end?

Mike [

 

[N2HIPSI]

Sorry I don't have an answer for you, but I do have a similar story which may point you in a different direction. I had a bad drain on my car as well. It would just die anytime, anywhere. I took it to my mechanic at rhe time and he had the car for two weeks. First, he could'nt get the car to give him a problem. Once it did, he drove himself crazy looking for it. He called me and told me to come get it because he had given up. Well he had a change of heart and went back out to the car and started looking around again. As he was holdin a meter to the fuse box, he lost his balance and slipped into the dash. When he did, it showed an interruption on the meter. What he found was a loose ground under the dash. Hope it helps.
N2hipsi

 

[G McCall]

Originally posted by N2HIPSI
Sorry I don't have an answer for you, but I do have a similar story which may point you in a different direction. I had a bad drain on my car as well. It would just die anytime, anywhere. I took it to my mechanic at rhe time and he had the car for two weeks. First, he could'nt get the car to give him a problem. Once it did, he drove himself crazy looking for it. He called me and told me to come get it because he had given up. Well he had a change of heart and went back out to the car and started looking around again. As he was holdin a meter to the fuse box, he lost his balance and slipped into the dash. When he did, it showed an interruption on the meter. What he found was a loose ground under the dash. Hope it helps.
N2hipsi

Now thats a happy ending story ! Someone was lucky that day.
Ahh....... those intermitten grimlins....

Sure hope we here the end of KH440's problem here.

 

[kh440]

Yeah, I hope so too.

 

[JFH]

Alarm system ? Radio,CD player even when there off they draw. A radio system may work OK but if it's going bad may draw excessive current. Has anything elec. been added to the car?

John

 

[kh440]

At one point yes it did have one of those urban assault stereo systems. Found yards of wire between the trunk and dash no longer connected to anything. Traced and removed all of that crap. thinking the problem was there somewhere. satisfied that I had all of it, got the correct radio harness plugs and adapters, wired a known good radio, and hoped that would do it. That may have slowed down the rate at which it goes dead, but problem persists. No alarm or fuel pump shut off that I can find, and the interior is pretty much gutted. Again the really strange part is that I don't remember having this problem until I had a new windshield put in?

 

[JFH]

Try disconecting your Alternator
John

 

[kh440]

Tried it..no change, ditto for the ecm.

 

[pracingrev1140]

i would take starter off and have tested may be starting to short out internally ie bad windings