Large amp draw when car off
Pro
Joined: Feb 2006
Posts: 671
Likes: 10
2021 C4 of the Year - Unmodified Finalist
what he said
I showed all this info to our head electrical guy at work.
He says, as I did, if it happens when the FUSES ARE REMOVED it has to be on the battery side of the fuse block
He said he would suspect the alternator. Disconnect the alternator and see of the drain disappears, (or test each diode). Also he wanted to know how you ruled out the battery?
good luck
He says, as I did, if it happens when the FUSES ARE REMOVED it has to be on the battery side of the fuse block
He said he would suspect the alternator. Disconnect the alternator and see of the drain disappears, (or test each diode). Also he wanted to know how you ruled out the battery?
good luck
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
I showed all this info to our head electrical guy at work.
He says, as I did, if it happens when the FUSES ARE REMOVED it has to be on the battery side of the fuse block
He said he would suspect the alternator. Disconnect the alternator and see of the drain disappears, (or test each diode). Also he wanted to know how you ruled out the battery?
good luck
He says, as I did, if it happens when the FUSES ARE REMOVED it has to be on the battery side of the fuse block
He said he would suspect the alternator. Disconnect the alternator and see of the drain disappears, (or test each diode). Also he wanted to know how you ruled out the battery?
good luck
Team Owner
Joined: Jan 2003
Posts: 20,326
Likes: 252
From: Summerland B.C. Canada
I am no electrical guru, but here is a question for those that are.
Since the primary side of a relay can allow current to pass through to ground, could the current show up on a meter testing a circuit that also has a relay, that is connected to the same ground as the other circuit ?
If so, maybe all of those circuits that show the same draw, all have a relay in the circuit ? ?
Since the primary side of a relay can allow current to pass through to ground, could the current show up on a meter testing a circuit that also has a relay, that is connected to the same ground as the other circuit ?
If so, maybe all of those circuits that show the same draw, all have a relay in the circuit ? ?
Drifting
Joined: Jun 2013
Posts: 1,590
Likes: 60
From: ft myers FL/Munising MI
glad you[re getting all the help.....getting way to technical for me....I only got a liberal arts degree....old eastern philosophy...if you can't find something where you"re looking, look somewhere else... maybe you ought to back up a bit and look for something simple or stupid....looked it over in the total darkness? started it in the dark?.....just my .02
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
glad you[re getting all the help.....getting way to technical for me....I only got a liberal arts degree....old eastern philosophy...if you can't find something where you"re looking, look somewhere else... maybe you ought to back up a bit and look for something simple or stupid....looked it over in the total darkness? started it in the dark?.....just my .02
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
I am no electrical guru, but here is a question for those that are.
Since the primary side of a relay can allow current to pass through to ground, could the current show up on a meter testing a circuit that also has a relay, that is connected to the same ground as the other circuit ?
If so, maybe all of those circuits that show the same draw, all have a relay in the circuit ? ?
Since the primary side of a relay can allow current to pass through to ground, could the current show up on a meter testing a circuit that also has a relay, that is connected to the same ground as the other circuit ?
If so, maybe all of those circuits that show the same draw, all have a relay in the circuit ? ?
The way Im measuring its simply draw off the battery load wise. There shouldn't be a load like that on more than one of those fusible links from the power distribution block.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Well todays pretty weather that was forecast is now rain 
But on a happy note I got my battery disconnect in I ordered and got it installed between rain bouts. Worked like a charm. Tighten the **** car cranks right up. Loosen 1/4 turn and it cuts all power to the car.
This is NOT a fix but something I wanted even when I fix this draw problem. As little as I drive the car it needs the battery disconnect even when its working right.
But on a happy note I got my battery disconnect in I ordered and got it installed between rain bouts. Worked like a charm. Tighten the **** car cranks right up. Loosen 1/4 turn and it cuts all power to the car.
This is NOT a fix but something I wanted even when I fix this draw problem. As little as I drive the car it needs the battery disconnect even when its working right.
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Michael S. Palmer
Race Director
Joined: Aug 2007
Posts: 11,889
Likes: 8
From: Whitefish Falls Ontario
St. Jude Donor '08-'09
Just started reading this thread. If I were chasing this problem, I would look at where I have power with the jump start block links disconnected. With A disconnected there should be no power to any fuses other than the ones powered by link M, which is for tail/cts fuse and light switch.. If B and C links are removed there should be no power to the two alternator wires.( especially if removed from alternator).. If link F and G are removed there s/b no power to the headlight door motor relays. Link J is the modulator valve and K the a/c blower, either relay or module, if these are disconnected there s/b no power..
So with all links disconnected and alt., RH and LH relays disconnected, modulator valve disconnected, a/c blower relay or module disconnected, + tail/ctsy and light switch, I would check all these points plus all the fuse sockets. If you still have a draw I would look at disconnecting the other fusible links plus anything off the starter..
So with all links disconnected and alt., RH and LH relays disconnected, modulator valve disconnected, a/c blower relay or module disconnected, + tail/ctsy and light switch, I would check all these points plus all the fuse sockets. If you still have a draw I would look at disconnecting the other fusible links plus anything off the starter..
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
The problem with the links is I cant find any identifying marks on them. So I cant tell what goes to what at the block itself.
I didn't get anything done today
Daughter called me at 9am wanting me to come over and help them put a transmission in her truck. Just got home at 5pm and I'm DEAD tired. Plus its raining lightly outside.....
Weather shows rain Sunday and Monday so it will be Tuesday before I can have a go at it again.
I didn't get anything done today
Daughter called me at 9am wanting me to come over and help them put a transmission in her truck. Just got home at 5pm and I'm DEAD tired. Plus its raining lightly outside.....
Weather shows rain Sunday and Monday so it will be Tuesday before I can have a go at it again.
Racer
Joined: Oct 2012
Posts: 265
Likes: 5
From: Phoenix AZ
Reading and following this with great interest. What a problem! Seams that everything that could be checked has been checked. Everything that could be pulled has been pulled. When you have eliminated the obvious, what remains, no matter how improbable must be the truth. So I'll offer up this...I've seen reference to it several times. Could your problem be weather related? Water or moisture getting into the car where a wire or wires are stripped or frayed, causing a short? Wish I could be there to help. I have an 87 also and want to see this conquered.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
That's planned to.
I just need weather and relatives not calling
Just ordered a ton of stuff to do the wheel bearings on the wifes bmw tonight. Nice $500 project for this week too
I just need weather and relatives not calling
Just ordered a ton of stuff to do the wheel bearings on the wifes bmw tonight. Nice $500 project for this week too
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 413
From: WV
A few years ago I had a 1.5 amp draw I couldn't find,drove me nuts for almost a year...Wasn't found until I replaced the starter .Seems the starter motor had a short causing the drain..Check for 12 volts at both the solinoid , and at the strap that connects the solinoid to the starter motor while turning the key to start...It only takes a few minites to check...WW
Last edited by WW7; Mar 22, 2015 at 10:30 AM.
1st Gear
Joined: Mar 2015
Posts: 1
Likes: 0
Same issue on 87
For what it's worth, mine was doing the exact same thing. Turned out to be a headlight motor that would operate just fine, however it did not develop enough torque to open the contact inside the headlight motor assembly. It had a very thin brush. I found it accidentally after hours with the Fluke. Find the grey three wire headlight motor plugs and unplug them and see if the problem goes away. You could try listening to the assembly when you plug it back in for any noise. Should be dead dead when the headlights are off so if you hear a little grunt or a momentary jump, that's the problem. On my bad one, (when the bat was charged), you could touch the headlight motor and it was warm. Hope this helps.
Since I bought my vette back in December its drained the battery to 0 volts every couple of days. I finally got a chance to test it to see how many amps I had draining.
2.64 amps
I pulled every fuse, every breaker in the fuse box and no change.
Pulled every relay I could find under the hood, unplugged the headlights, wiper motor, etc.
Still 2.64 to 2.66.
Suggestions on what might pull that much?
I changed stereos since buying it and it didn't change the running down the battery any. No amp just radio in dash.
2.64 amps
I pulled every fuse, every breaker in the fuse box and no change.
Pulled every relay I could find under the hood, unplugged the headlights, wiper motor, etc.
Still 2.64 to 2.66.
Suggestions on what might pull that much?
I changed stereos since buying it and it didn't change the running down the battery any. No amp just radio in dash.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
For what it's worth, mine was doing the exact same thing. Turned out to be a headlight motor that would operate just fine, however it did not develop enough torque to open the contact inside the headlight motor assembly. It had a very thin brush. I found it accidentally after hours with the Fluke. Find the grey three wire headlight motor plugs and unplug them and see if the problem goes away. You could try listening to the assembly when you plug it back in for any noise. Should be dead dead when the headlights are off so if you hear a little grunt or a momentary jump, that's the problem. On my bad one, (when the bat was charged), you could touch the headlight motor and it was warm. Hope this helps.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
A few years ago I had a 1.5 amp draw I couldn't find,drove me nuts for almost a year...Wasn't found until I replaced the starter .Seems the starter motor had a short causing the drain..Check for 12 volts at both the solinoid , and at the strap that connects the solinoid to the starter motor while turning the key to start...It only takes a few minites to check...WW
Team Owner
Joined: Sep 2003
Posts: 25,398
Likes: 2,743
Just another WAG? Maybe -
I thought the H/L's had been disconnected previously also.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
I thought you had removed the starter once already BUT maybe just maybe with so many oddities the ignition side of the starter is connected to the ignition switch and if you maybe had a bad switch or a starter problem that pushed back through the solenoid wire then it might create every issue you've got.
Just another WAG? Maybe -
I thought the H/L's had been disconnected previously also.
Just another WAG? Maybe -
I thought the H/L's had been disconnected previously also.
Starter wasn't touched since the draw isn't effected by it being connected. But I guess it could be back fed somehow.
Next test is for voltage on the fuses with the fuses pulled. Just waiting on the rain to stop.