Large amp draw when car off
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Its got to be a crushed wired. That's the only thing that makes sense. But what I don't get is what can pull 2.6 amps with the car off? Nothing appears to be running. Nothing works that shouldn't work with the key off. That's the part that's driving me up the wall. If its shorting over to places it shouldn't then I should have power leaking to something it shouldn't.
Course I just thought of something to try to see if its short like that.
I need to test for voltage on fuses that shouldn't have power with the key off.
Anyone want to volunteer on their car to find the fuses that are unpowered when the key is off?
Course I just thought of something to try to see if its short like that.
I need to test for voltage on fuses that shouldn't have power with the key off.
Anyone want to volunteer on their car to find the fuses that are unpowered when the key is off?
Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
The FSM under FUSE BOX details shows when each circuit is powered. Each and everyone. HOT IN RUN, BULB TEST, START, AT ALL TIMES should be in a dark framed note with each circuit. All in one spot in the FSM. I guessed that you had already done that.
Safety Car
Joined: Sep 2004
Posts: 3,953
Likes: 550
From: Mission Viejo CA
In all of this thread, you've never mentioned the FSM. It sounds like you're a pretty talented guy, but without the FSM, you are doing a lot of shooting in the dark. Have you printed out the diagram in post #14? Do you have the FSM?
A hard short to ground WILL smoke! What is the resistance measurement from your 12v. jump start block to ground? About 5 ohms?
A hard short to ground WILL smoke! What is the resistance measurement from your 12v. jump start block to ground? About 5 ohms?
Last edited by Hot Rod Roy; Mar 18, 2015 at 04:19 PM.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Ive got alldata which covers vehicles till 2006 I think. That's when I dropped my subscription.
Wiring isnt very user friendly in alldata.
I added the diagram from post #14 to my database so Ive got it on the tablet when Im at the car.
The reason I didn't check earlier in the process for what had or didn't have power is everything works fine. Just kills the battery. But with all fuses pulled I should be able to figure whats leeching across what. Course with 6 of 7 fusible links showing the draw it may show power all over the place.
I haven't been able to work on it today so far but Im about to get out there and start on it shortly. Just got home.
I'll probably order the fsm for it since Im not allergic to more reference materials.
Wiring isnt very user friendly in alldata.
I added the diagram from post #14 to my database so Ive got it on the tablet when Im at the car.
The reason I didn't check earlier in the process for what had or didn't have power is everything works fine. Just kills the battery. But with all fuses pulled I should be able to figure whats leeching across what. Course with 6 of 7 fusible links showing the draw it may show power all over the place.
I haven't been able to work on it today so far but Im about to get out there and start on it shortly. Just got home.
I'll probably order the fsm for it since Im not allergic to more reference materials.
Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
These are from an '86 FSM and you could assume maybe '87 similar OR maybe "c4cruiser" can confirm:
INJ 1 & 2 = HIR, BT or ST
BRAKE = HAAT
Rear Hatch CB = HAAT
TAIL = HAAT
CTSY/CLK = HAAT
ECM/IGN = HIR, BT or ST
VATS = HAAT
AC = HIR
TURN/BU = HIR, BT or ST
STOP/HAZ = HAAT
RADIO = HIA or HIR
C FAN = HIR
CRUISE = HIR, BT or HIR
ACC CB = HAAT
Pow Win CB = HIR
CLST = HIR, BT or ST
LCD = HAAT
WIPER = HIA or HIR
FP = Supplied power from FP relay
RR DEF CB = HAAT
HAAT - Hot At All Times, HIA - Hot In Accesory, HIR - Hot In Run, BT - Bulb Test, ST - Start, CB - Circuit Breaker
If you've questions about one that maybe isn't in the list just ask.
INJ 1 & 2 = HIR, BT or ST
BRAKE = HAAT
Rear Hatch CB = HAAT
TAIL = HAAT
CTSY/CLK = HAAT
ECM/IGN = HIR, BT or ST
VATS = HAAT
AC = HIR
TURN/BU = HIR, BT or ST
STOP/HAZ = HAAT
RADIO = HIA or HIR
C FAN = HIR
CRUISE = HIR, BT or HIR
ACC CB = HAAT
Pow Win CB = HIR
CLST = HIR, BT or ST
LCD = HAAT
WIPER = HIA or HIR
FP = Supplied power from FP relay
RR DEF CB = HAAT
HAAT - Hot At All Times, HIA - Hot In Accesory, HIR - Hot In Run, BT - Bulb Test, ST - Start, CB - Circuit Breaker
If you've questions about one that maybe isn't in the list just ask.
Last edited by WVZR-1; Mar 18, 2015 at 06:10 PM.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Thanks. Its clouding up here so I put the cover on the car for tonight. Its supposed to rain tonight all day tomorrow and stop day after tomorrow morning. Then clear skies for the rest of the forecast. So I get a day off it seems
Will get back on it when the rain passes.
Again thanks to everyone helping !
Will get back on it when the rain passes.
Again thanks to everyone helping !
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
If I leave it connected it goes to 9 volts in 48 hrs or so and 0 or .4 volts in a 4 days or a week.
Its been undone since sunday and shows 12.8 volts still as of today and will crank the car fine. So the batteries fine.
Plus Im measuring a 2.60 amp drain all the time. It should be .5 amps or less. At 2.60 amps it will kill any battery within a day or two.
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Burning Brakes
Joined: Apr 2011
Posts: 917
Likes: 25
From: College Station Tx
Its completely ruled out.
If I leave it connected it goes to 9 volts in 48 hrs or so and 0 or .4 volts in a 4 days or a week.
Its been undone since sunday and shows 12.8 volts still as of today and will crank the car fine. So the batteries fine.
Plus Im measuring a 2.60 amp drain all the time. It should be .5 amps or less. At 2.60 amps it will kill any battery within a day or two.
If I leave it connected it goes to 9 volts in 48 hrs or so and 0 or .4 volts in a 4 days or a week.
Its been undone since sunday and shows 12.8 volts still as of today and will crank the car fine. So the batteries fine.
Plus Im measuring a 2.60 amp drain all the time. It should be .5 amps or less. At 2.60 amps it will kill any battery within a day or two.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Ok. Probably not. My last battery tested ok (or at least they said it did), would charge up just fine, but was good for a few starts before it died. Took it back and had it retested by a different tech and it tested bad. New battery, no more issues. Just wondering if a shorted battery cell will cause the drain.
Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
https://www.corvetteforum.com/forums...nvertible.html
'vert courtesy lights in the boot area and spare tire light.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Lights don't come on when I open the door and nothing comes on under the car so Im guessing that's not doing it.
But I haven't been able to see or unplug the courtesy timer yet and I plan on it just to see what happens.
I have all the symptoms of a bad timer.
Lights don't come on opening the door but do with the headlight ****.
Switches on door do not open convertible hatch panel but the one in the console lid area does.
But getting to the thing is proving difficult.
As soon as the rain stops Im going to pull the dash top pad off again and see if I can get to it that way.
But I haven't been able to see or unplug the courtesy timer yet and I plan on it just to see what happens.
I have all the symptoms of a bad timer.
Lights don't come on opening the door but do with the headlight ****.
Switches on door do not open convertible hatch panel but the one in the console lid area does.
But getting to the thing is proving difficult.
As soon as the rain stops Im going to pull the dash top pad off again and see if I can get to it that way.
Burning Brakes
Joined: Apr 2011
Posts: 917
Likes: 25
From: College Station Tx
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
I checked those when I installed the new locks the other day. They should of listed "some assembly required" on those lock cylinders with keys I bought. Not fun.
Sitting here watching it pour outside. But to be honest I needed a day off to rest so I guess the rains not that bad. But tomorrow I'll be back at it.
Sitting here watching it pour outside. But to be honest I needed a day off to rest so I guess the rains not that bad. But tomorrow I'll be back at it.
Safety Car
Joined: Sep 2004
Posts: 3,953
Likes: 550
From: Mission Viejo CA
Since you've got everybody throwing Wild Guesses, let's join the WAG game!
Fact one: Most of these WAG's shouldn't be at all possible if you have removed all of the fuses and CB's in you fuse panel.
Fact two: A 2.5A current draw is not a dead short to ground. (The car wouldn't run if you had a dead short).
Fact three: Your battery is good! Even a new battery would be dead in a few days with this current draw.
Fact four: Your measurement of the same current draw thru several wires connected to your jump start block only make sense if those wires are connected together somewhere else. They shouldn't be!
So, where is the current going?
With all of your fuses and CB's removed, battery connected, and your ignition switch on, are there any empty fuse locations that have voltage on BOTH sides of the fuse terminals? All fuses/CB's should be dead on one side. Does anything work with all fuses removed?
Fact one: Most of these WAG's shouldn't be at all possible if you have removed all of the fuses and CB's in you fuse panel.
Fact two: A 2.5A current draw is not a dead short to ground. (The car wouldn't run if you had a dead short).
Fact three: Your battery is good! Even a new battery would be dead in a few days with this current draw.
Fact four: Your measurement of the same current draw thru several wires connected to your jump start block only make sense if those wires are connected together somewhere else. They shouldn't be!
So, where is the current going?
With all of your fuses and CB's removed, battery connected, and your ignition switch on, are there any empty fuse locations that have voltage on BOTH sides of the fuse terminals? All fuses/CB's should be dead on one side. Does anything work with all fuses removed?
Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
Your rain is going to be my SNOW in the AM according to the guys that are paid to "guess at it"! The weather that is.
I was trying to find the construction of the fuse box that I have on a machine likely with a failed hard-drive showing the "buss-bar" construction etc - that would explain a potential situation where the wire insulation deteriorates and the fuse box becomes one large + terminal/circuit. That is the reason I also suggested testing each fusible link "separately" because some just do major components. I actually thought the fuse box had likely been checked while everything was removed.
Hey LD - Don't see you around much. How go things?
Fact one: Most of these WAG's shouldn't be at all possible if you have removed all of the fuses and CB's in you fuse panel.
Fact four: Your measurement of the same current draw thru several wires connected to your jump start block only make sense if those wires are connected together somewhere else. They shouldn't be!
So, where is the current going?
With all of your fuses and CB's removed, battery connected, and your ignition switch on, are there any empty fuse locations that have voltage on BOTH sides of the fuse terminals? All fuses/CB's should be dead on one side. Does anything work with all fuses removed?
Fact four: Your measurement of the same current draw thru several wires connected to your jump start block only make sense if those wires are connected together somewhere else. They shouldn't be!
So, where is the current going?
With all of your fuses and CB's removed, battery connected, and your ignition switch on, are there any empty fuse locations that have voltage on BOTH sides of the fuse terminals? All fuses/CB's should be dead on one side. Does anything work with all fuses removed?
I was trying to find the construction of the fuse box that I have on a machine likely with a failed hard-drive showing the "buss-bar" construction etc - that would explain a potential situation where the wire insulation deteriorates and the fuse box becomes one large + terminal/circuit. That is the reason I also suggested testing each fusible link "separately" because some just do major components. I actually thought the fuse box had likely been checked while everything was removed.
Hey LD - Don't see you around much. How go things?
Last edited by WVZR-1; Mar 19, 2015 at 09:42 PM.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Here's a fun fact: the center console hatch switch gets its ground from the starter solenoid. You cannot open the hatch while the starter is cranking.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Any negatives to straight wiring the courtesy timer and doing away with it?
Since I will be removing the dash pad to get to this thing and don't have one to replace it with on hand Id rather rig up a bypass than wait. Dash pad isn't that fun to remove constantly
Since I will be removing the dash pad to get to this thing and don't have one to replace it with on hand Id rather rig up a bypass than wait. Dash pad isn't that fun to remove constantly