Electrical Help Needed....... Please
Thread Starter
Racer
Joined: Sep 2000
Posts: 291
Likes: 1
From: East TX
Electrical Help Needed....... Please
I have an 85 with a short somewhere in the system. I hooked-up my ampmeter and it shows a .5 amp draw. I've pulled all the fuses with no results. Does anybody have an idea on where to go from here.
thanks for your help,
david
thanks for your help,
david
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
Re: Electrical Help Needed....... Please (david85)
Try disconecting the alt. the diodes may have a short. I would start by disonecting the alt. then keep diconecting every thing to isolate problem The starter would be my next choice then look at any thing that has a direct +12 VDC input such as ECM, Radio, ect.. till the problem is isolated. Somthing has a short to ground and you have already pulled all the fuses so the next step is to start disconecting items that have a strait 12 VDC input.
Thread Starter
Racer
Joined: Sep 2000
Posts: 291
Likes: 1
From: East TX
Re: Electrical Help Needed....... Please (david85)
I have read somewhere on how to trace through the fuseable links, but not sure where to start.... It had a bad steering column and tonight I removed to old one, and it still shows the drain... :nonod:
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Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
Re: Electrical Help Needed....... Please (david85)
.
On my 84 most of the fuseable links are near the starter but they are all tied to the same lug so isolating them would be dificult. Have you tried disconecting the Alt., ECM and radio yet? Any of those could cause your problem if there was a short because they all have a batery lead of 12V that does not go through the fuse box.
I have read somewhere on how to trace through the fuseable links, but not sure where to start.... It had a bad steering column and tonight I removed to old one, and it still shows the drain... :nonod:
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Electrical Help Needed....... Please (david85)
Check for vanity lights left on and the console glove box light. Check for the underhood lights being on. If you have an aftermarket radio or audio amplifiers or alarm, disconnect them one at a time. Several CFers have found power seat switches stuck on, check yours. Remove the nut on the jump start bolt behind the battery. This terminal has 8 wires on it that have fusible links. Watch your ammeter while you hold the lugs in contact with the bolt and then remove a wire at a time. If the ammeter drops, trace that wire. All of the wires are red. If you still have 0.5 amps of leakage, you have several circuit breakers to check out, one goes to the hatch release relay, one powers door locks and seat motors. One powers the window switches. One powers the defogger relay. Check all circuits that are powered with a circuit breaker. A compass held close to the wire will tell you if 0.5 amps is flowing in that wire, or else get a clamp on d.c. ammeter.
Thread Starter
Racer
Joined: Sep 2000
Posts: 291
Likes: 1
From: East TX
Re: Electrical Help Needed....... Please (david85)
Thanks to all for the advice. I am using a volt/ohm meter in series between the positive battery terminal, and the battery cable. I have gone out at night and connected the battery to look for any lights staying on, but there is none. The suggestion of the seats might be a possiblity since it was haveing problems moving when I looked at the car. I'll also check the terminals behind the battery. I've removed the battery and had it checked, and it was good. Currentlly I leave the positive cable off so I don't have to recharge the battery each time I want to troubleshoot the problem.
If anybody else has any more ideas please let me know...
thanks,
david
If anybody else has any more ideas please let me know...
thanks,
david
Thread Starter
Racer
Joined: Sep 2000
Posts: 291
Likes: 1
From: East TX
Re: Electrical Help Needed....... Please (david85)
Guess I should have clairified. I'm useing the amp side of my volt/ohm meter and the digital read-out is where I'm getting the .5 amps. This is how we check current draw on the aircraft I maintain so I thought this would be good enough. If I need a clamp around type I'll try and find one.. But I know if I leave the battery connected overnight, It'll be dead in the morning.
thanks again,
david
thanks again,
david
Thread Starter
Racer
Joined: Sep 2000
Posts: 291
Likes: 1
From: East TX
Re: Electrical Help Needed....... Please (david85)
One other thing, I have used the trouble light between the positive battery post, and the cable and it lights due to the draw. I only used this as a visual reference while pulling the fuses. (None caused the light to go out)
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
Re: Electrical Help Needed....... Please (david85)
Have you tried disconecting any of the assy's that dont go through the fuse box yet????????????????????????????????
If you pull all of the fuses and it still has the same .5 Amp draw then it is not one of the fused assy's. Try disconecting the Assy's that have a strait +12 VDC from the battery such as the altenator , Radio, ECM, ect... untill the curent drops to 0 amps
If you pull all of the fuses and it still has the same .5 Amp draw then it is not one of the fused assy's. Try disconecting the Assy's that have a strait +12 VDC from the battery such as the altenator , Radio, ECM, ect... untill the curent drops to 0 amps
Instructor
Joined: Nov 2002
Posts: 131
Likes: 0
From: Tacoma Wa
Re: Electrical Help Needed....... Please (ejfagala)
If u pulled all the fuses/circuit breakers & still have draw then I'll bet its a short of the cables that go behind engine & have been known to chafe on the transmission housing causing a short.
just my 2 cents
;)
just my 2 cents
;)
Thread Starter
Racer
Joined: Sep 2000
Posts: 291
Likes: 1
From: East TX
Re: Electrical Help Needed....... Please (david85)
I have disconnected the alternator and radio.... No help :nonod:
My next plan after reading the service manual id to try and disconnect the fuseable links? Somebody had said they connect somewhere right behind the battery.....
I've still got the steering column out of the car so I think I can disregard anything that goes through the switch..
My next plan after reading the service manual id to try and disconnect the fuseable links? Somebody had said they connect somewhere right behind the battery.....
I've still got the steering column out of the car so I think I can disregard anything that goes through the switch..
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Electrical Help Needed....... Please (david85)
Go back and read my first post and follow my suggestions! There isn't a special place on your left rear tire that you can kick and fix your leakage current. You have to do the work!
Thread Starter
Racer
Joined: Sep 2000
Posts: 291
Likes: 1
From: East TX
Re: Electrical Help Needed....... Please (david85)
Does anybody know, does the 85 have a ground wire on one of the starter bolts? I had been restoring a friends 70 and he had the same problem of the battery going dead over time. It turned out somebody had added this wire to the batteryside of the starter... Just wondered if lighting could strike twice.