4 amp drain on battery-all fuses pulled
Thread Starter
Racer
Joined: May 2009
Posts: 256
Likes: 0
4 amp drain on battery-all fuses pulled
Ok for those that dont know... Swapped in a 95 LT1 and zf6 into an 87 vette.
some background:
We messed with alot of wiring here which I had my buddy do most of cuz I am not good with electricals. Wiring harness came with engine/trans with comp which "LT1 wiring" checked it out and cleaned it up. Had to connect harness into chassis wiring for gauges and for it to start and shut off properly..
Now I got the alternator tested at autozone which passed... and a brand new battery hoping the old one was not good.
I pulled every fuse possible in the car and I still have 3.5 to 4 amps being drained with the car off.
What could drain it? Can it be a short?
some background:
We messed with alot of wiring here which I had my buddy do most of cuz I am not good with electricals. Wiring harness came with engine/trans with comp which "LT1 wiring" checked it out and cleaned it up. Had to connect harness into chassis wiring for gauges and for it to start and shut off properly..
Now I got the alternator tested at autozone which passed... and a brand new battery hoping the old one was not good.
I pulled every fuse possible in the car and I still have 3.5 to 4 amps being drained with the car off.
What could drain it? Can it be a short?
Racer
Joined: Oct 2006
Posts: 438
Likes: 14
From: Tucson/Santa Paula AZ/CA
2017 C4 of Year Finalist
Burning Brakes
Joined: Oct 2010
Posts: 1,037
Likes: 28
From: Montclair New Jersey
I had a drain over the summer also. I pulled all the fuses with no help. Finally it was the main relay and link to the main fan. I have a 1986 with a L-98. Just my two cents.
good luck
good luck
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
Not all current and circuits go thru the fuses. Testing the alternator at AZ may not show up the problem. Just reconnect your ammeter to the battery and disconnect the alternator. Then you can find out if it is the cause of the excess current draw.
If the alternator is good, then I would start disconnecting the fuse links. That may lead you to the answer.
If the alternator is good, then I would start disconnecting the fuse links. That may lead you to the answer.
Drifting
Joined: Sep 2002
Posts: 1,642
Likes: 0
From: Suwanee,Ga
Ok for those that dont know... Swapped in a 95 LT1 and zf6 into an 87 vette.
some background:
We messed with alot of wiring here which I had my buddy do most of cuz I am not good with electricals. Wiring harness came with engine/trans with comp which "LT1 wiring" checked it out and cleaned it up. Had to connect harness into chassis wiring for gauges and for it to start and shut off properly..
Now I got the alternator tested at autozone which passed... and a brand new battery hoping the old one was not good.
I pulled every fuse possible in the car and I still have 3.5 to 4 amps being drained with the car off.
What could drain it? Can it be a short?
some background:
We messed with alot of wiring here which I had my buddy do most of cuz I am not good with electricals. Wiring harness came with engine/trans with comp which "LT1 wiring" checked it out and cleaned it up. Had to connect harness into chassis wiring for gauges and for it to start and shut off properly..
Now I got the alternator tested at autozone which passed... and a brand new battery hoping the old one was not good.
I pulled every fuse possible in the car and I still have 3.5 to 4 amps being drained with the car off.
What could drain it? Can it be a short?
Could be a short... 4 amps isn't a dead short, though because a fuse would go or a fuse link would burn up.
When you say " fuses " and you mean the insert type in the fuse box, you have not disconnected all circuits.
There are fuse links for at least six circuits.
Follow the red Battery (+) wire... [ this will be sort of like taking that red pill in the Marix?].
It will go to a dist. block behind the batt. [ pretty sure .. using a '89 wiring dia?].
Each one of those ringer terminal wires is a Fuse Link.
Alt will be one, Fan motor will be one Blower motor will be one. etc.
Check those and you will find the current draw, or at least which red wire it is on. Traceable if you have a meter . Simple if you have a FSM after that.
What might it be? Sounds like a lamp at 48 watts?
TJM
Last edited by TJM; Oct 26, 2011 at 08:17 AM. Reason: cause
Melting Slicks
Joined: Dec 2008
Posts: 2,772
Likes: 64
From: Mystic CT
I am not sure about your car but my 91 has 8 more fuses behind the passenger side knee bolster. At the least you might go under the hood and start unplugging things that you can easily get to and then like the OP said go for the fuse links.
Thread Starter
Racer
Joined: May 2009
Posts: 256
Likes: 0
Connected... Though i tried it once with it onnected and thought is lost charge... then after i tested at AZ, I tested it again with multimeter and didnt seem to do anything.... Idk I will try again to make sure.
Ur asking cuz it the Diodes that can go bad in alternator and pull a chartge right? Does the AZ test not cover that?
Ur asking cuz it the Diodes that can go bad in alternator and pull a chartge right? Does the AZ test not cover that?
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Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Thread Starter
Racer
Joined: May 2009
Posts: 256
Likes: 0
Could be a short... 4 amps isn't a dead short, though because a fuse would go or a fuse link would burn up.
When you say " fuses " and you mean the insert type in the fuse box, you have not disconnected all circuits.
There are fuse links for at least six circuits.
Follow the red Battery (+) wire... [ this will be sort of like taking that red pill in the Marix?].
It will go to a dist. block behind the batt. [ pretty sure .. using a '89 wiring dia?].
Each one of those ringer terminal wires is a Fuse Link.
Alt will be one, Fan motor will be one Blower motor will be one. etc.
Check those and you will find the current draw, or at least which red wire it is on. Traceable if you have a meter . Simple if you have a FSM after that.
What might it be? Sounds like a lamp at 48 watts?
TJM
When you say " fuses " and you mean the insert type in the fuse box, you have not disconnected all circuits.
There are fuse links for at least six circuits.
Follow the red Battery (+) wire... [ this will be sort of like taking that red pill in the Marix?].
It will go to a dist. block behind the batt. [ pretty sure .. using a '89 wiring dia?].
Each one of those ringer terminal wires is a Fuse Link.
Alt will be one, Fan motor will be one Blower motor will be one. etc.
Check those and you will find the current draw, or at least which red wire it is on. Traceable if you have a meter . Simple if you have a FSM after that.
What might it be? Sounds like a lamp at 48 watts?
TJM
Thread Starter
Racer
Joined: May 2009
Posts: 256
Likes: 0
So just take one off, then test battery again to see if it is still drawing, correct? If I isolate the problem to one wire though, my next question would be what to do with it... nothing is on in the car... would I just leave that wire off?
Burning Brakes
Joined: Dec 2008
Posts: 1,021
Likes: 7
From: Morgan Hill and Marina California
Set the meter up to measure the current draw. It should still be 4A.
Now remove one of the fusable link wires at a time. Figure out which one
causes the current draw to drop when removed. Then use the FSM
to figure out what's powered by that fusible link.
Now remove one of the fusable link wires at a time. Figure out which one
causes the current draw to drop when removed. Then use the FSM
to figure out what's powered by that fusible link.
Thread Starter
Racer
Joined: May 2009
Posts: 256
Likes: 0
So found the draw... It was from one of those links... it happened to go to the ignition system/purge valve. Tried to single out the device but with all of it unhooked it still was drawing. Idk if it went to anything else.
We decided for now to hook a relay on it So it only turns on when the car keys are turned to on
We decided for now to hook a relay on it So it only turns on when the car keys are turned to on
