Large amp draw when car off
Oil Producer
Joined: Apr 2014
Posts: 9,377
Likes: 2,737
im sure u have looked, but i did a couple searches on other threads.
https://www.corvetteforum.com/forums...etc-ideas.html
https://www.corvetteforum.com/forums...ease-help.html
this second thread seems to have some things in common with the draw across all the wires.
it was never officially resolved but i bet it was a ground as that was the last thing brought up on the thread.
on that note, could it be like that thread suggested and if a ground is bad, the power goes hunting for ground elsewhere and tracels through another circut to get it??
Last edited by VikingTrad3r; Mar 17, 2015 at 09:40 PM.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Well the guy with the problem on the right hand conversion is identical to my symptoms but he hasn't posted since march of last year. I sent him a message to see if he found his drain.
Good news though I just got the drivers door lock swapped out
So I can lock that door now. Still have the passenger door to do sometime. This was NOT fun but rewarding getting it done.
Car didn't come with door keys. The guy died that owned the car before me (bought it from his wife). She couldn't find any key but the ignition key.
Good news though I just got the drivers door lock swapped out
So I can lock that door now. Still have the passenger door to do sometime. This was NOT fun but rewarding getting it done.Car didn't come with door keys. The guy died that owned the car before me (bought it from his wife). She couldn't find any key but the ignition key.
Team Owner
Joined: Sep 2003
Posts: 25,397
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I have no idea how you're doing your parasitic draw test and I'm not being critical but yours certainly is an "oddity". I believe if it were me I'd tackle it in this fashion. Will it help? I have no idea but it might give you something that could be used for comparable comparisons.
People do parasitic checks a couple different ways, through the + cable or the - cable.
You have 6 you say that show the draw and 1 that doesn't. I would construct a 10ga lead with alligator clips and isolate the fusible links by insulating the ring terminals and leave them disconnected. Do the parasitic check using the negative terminal and connect your lead to each ring terminal of the fusible links one at a time to the +post and note the value of each. You would think that possibly you might have different values and if one was greater than all others that maybe that circuit is the problem and you check that circuit. I would think it's possible if your problem was a ground that you would get results that you have.
Doing a test of each separately I believe would take 30 minutes. What's to loose? If this is how you're doing it I apologize. I'm not trying to be critical.
It's difficult to sort through the FSM looking for shared grounds but if 1 circuit displayed a larger draw it could certainly reduce the effort.
People do parasitic checks a couple different ways, through the + cable or the - cable.
You have 6 you say that show the draw and 1 that doesn't. I would construct a 10ga lead with alligator clips and isolate the fusible links by insulating the ring terminals and leave them disconnected. Do the parasitic check using the negative terminal and connect your lead to each ring terminal of the fusible links one at a time to the +post and note the value of each. You would think that possibly you might have different values and if one was greater than all others that maybe that circuit is the problem and you check that circuit. I would think it's possible if your problem was a ground that you would get results that you have.
Doing a test of each separately I believe would take 30 minutes. What's to loose? If this is how you're doing it I apologize. I'm not trying to be critical.
It's difficult to sort through the FSM looking for shared grounds but if 1 circuit displayed a larger draw it could certainly reduce the effort.
Last edited by WVZR-1; Mar 18, 2015 at 09:33 AM.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
I have the positive cable connected on the battery all the time.
I have the ground cable removed since its the safest with the tight space of the corvettes battery tray deal.
One lead from the meter is connected to the ground post of the battery the other to the disconnected ground lead from the car.
When I test distribution point behind the battery I removed all wires from the post there.
I then tested the lead from the positive side of the battery first. No draw. (this is because with them all disconnected its technically always connect )
Next I touched each of the other leads from that stud one at a time to the lead that comes from the positive side of the battery that goes to that stud.
All of the wires but one causes the draw to appear.
I have the ground cable removed since its the safest with the tight space of the corvettes battery tray deal.
One lead from the meter is connected to the ground post of the battery the other to the disconnected ground lead from the car.
When I test distribution point behind the battery I removed all wires from the post there.
I then tested the lead from the positive side of the battery first. No draw. (this is because with them all disconnected its technically always connect
)Next I touched each of the other leads from that stud one at a time to the lead that comes from the positive side of the battery that goes to that stud.
All of the wires but one causes the draw to appear.
Last edited by crowz; Mar 18, 2015 at 11:55 AM.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
I'll shoot some pics in a bit showing what Im doing to test. Will help others to probably that need to do this kind of testing.
That way we will all be on the same page in case someone see's something I could try that I haven't tried yet too.
That way we will all be on the same page in case someone see's something I could try that I haven't tried yet too.
Melting Slicks
Joined: Feb 2003
Posts: 2,677
Likes: 812
From: Saskatoon Sask.
I have the positive cable connected on the battery all the time.
I have the ground cable removed since its the safest with the tight space of the corvettes battery tray deal.
One lead from the meter is connected to the ground post of the battery the other to the disconnected ground lead from the car.
When I test distribution point behind the battery I removed all wires from the post there.
I then tested the lead from the positive side of the battery first. No draw. (this is because with them all disconnected its technically always connect )
Next I touched each of the other leads from that stud one at a time to the lead that comes from the positive side of the battery that goes to that stud.
All of the wires but one causes the draw to appear.
I have the ground cable removed since its the safest with the tight space of the corvettes battery tray deal.
One lead from the meter is connected to the ground post of the battery the other to the disconnected ground lead from the car.
When I test distribution point behind the battery I removed all wires from the post there.
I then tested the lead from the positive side of the battery first. No draw. (this is because with them all disconnected its technically always connect
)Next I touched each of the other leads from that stud one at a time to the lead that comes from the positive side of the battery that goes to that stud.
All of the wires but one causes the draw to appear.
Just noticed you are from Alabama, so I guess no winter there. However, if I am reading correctly, you mention it has been there since you bought it. May have had this condition for some time.
Last edited by arbee; Mar 18, 2015 at 12:10 PM.
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Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Grasping at straws here but it doesn't seem to be a simple deal. Have you seen or smelled any sign of mice from over the winter? If they have chewed through the insulation of the wires at any point, the six wires could be touching. Then the current draw you are seeing would do exactly as you describe.
Just noticed you are from Alabama, so I guess no winter there. However, if I am reading correctly, you mention it has been there since you bought it. May have had this condition for some time.
Just noticed you are from Alabama, so I guess no winter there. However, if I am reading correctly, you mention it has been there since you bought it. May have had this condition for some time.
As for cold....
Team Owner
Joined: Sep 2003
Posts: 25,397
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That's why I thought you might move "out of the box". Eliminate the + cable which I'm guessing is always connected also to the starter (unless it's still disconnected) and there's I think on an '87 another pig-tail to the + cable. I thought best to maybe get rid of all of this for testing. I'd maybe confirm the - cable is properly grounded and the primary ground straps from the engine block etc. are in the appropriate locations, clean and secure.
Last edited by WVZR-1; Mar 18, 2015 at 12:41 PM.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
That's why I thought you might move "out of the box". Eliminate the + cable which I'm guessing is always connected also to the starter (unless it's still disconnected) and there's I think on an '87 another pig-tail to the + cable. I thought best to maybe get rid of all of this for testing.
My next test is to unplug the lcd display. I cant see it doing anything with all the fuses pulled but who knows.
Team Owner
Joined: Sep 2003
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I would put the car back to as close to assembled as possible and do the test the way I suggested. I had an print of the way a period correct fuse box is constructed but I believe it's on a failed hard-drive or I'd post it for you. The fuse-box is very complicated internally with buss-bars etc.
Pro
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2021 C4 of the Year - Unmodified Finalist
JM2cW
You have a short to ground before the wire bundle.
The only way that much current can get to ground without starting to smoke is if there is a short to ground.
Instead of checking amperage draw try seeing where the voltage drops quit. Once you find zero voltage drop you are past the point of the short to ground in the circuit.
Like I said JM2cW
The only way that much current can get to ground without starting to smoke is if there is a short to ground.
Instead of checking amperage draw try seeing where the voltage drops quit. Once you find zero voltage drop you are past the point of the short to ground in the circuit.
Like I said JM2cW
Team Owner
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A weather station is a very interesting piece. My anemometer (wind-speed/direction is busted but I keep mine on Weather Underground and there are maybe 20 more in the area.
http://www.wunderground.com/personal...HARL16#history
I get maybe 4500 hits a month on mine most months. I'm pretty rural and I believe many that are close use it regularly.
http://www.wunderground.com/personal...HARL16#history
I get maybe 4500 hits a month on mine most months. I'm pretty rural and I believe many that are close use it regularly.
Last edited by WVZR-1; Mar 18, 2015 at 01:15 PM.
Melting Slicks
Joined: Feb 2003
Posts: 2,677
Likes: 812
From: Saskatoon Sask.
You have a short to ground before the wire bundle.
The only way that much current can get to ground without starting to smoke is if there is a short to ground.
Instead of checking amperage draw try seeing where the voltage drops quit. Once you find zero voltage drop you are past the point of the short to ground in the circuit.
Like I said JM2cW
The only way that much current can get to ground without starting to smoke is if there is a short to ground.
Instead of checking amperage draw try seeing where the voltage drops quit. Once you find zero voltage drop you are past the point of the short to ground in the circuit.
Like I said JM2cW
Pro
Joined: Feb 2006
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2021 C4 of the Year - Unmodified Finalist
just to clarify
What I said in my head but forgot to post was: If you take the fuses OUT and you still have current flow the source of the issue has to be between the battery and the fuse block. It will not be under the dash (past the fuse block)
There is a path to ground between the battery (source) and the fuse.
Like I said, JM2cW
There is a path to ground between the battery (source) and the fuse.
Like I said, JM2cW
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
A weather station is a very interesting piece. My anemometer (wind-speed/direction is busted but I keep mine on Weather Underground and there are maybe 20 more in the area.
http://www.wunderground.com/personal...HARL16#history
I get maybe 4500 hits a month on mine most months. I'm pretty rural and I believe many that are close use it regularly.
http://www.wunderground.com/personal...HARL16#history
I get maybe 4500 hits a month on mine most months. I'm pretty rural and I believe many that are close use it regularly.