Battery Drain
Cruising
Joined: May 2011
Posts: 11
Likes: 0
Your car should be able to sit 30-60 days at a time without a problem!!! 
Something is wrong. Your best bet is to use an AMP Meter and determine how much current the car draws when it is off and the electrical system goes to sleep.
I went out to my 02 Z06 and took the readings just a few minutes ago!
Disconnect the negative battery cable, install an AMP Meter capable of reading at least 10 amps between the battery terminal and the cable.
Negative meter lead on the negative battery terminal and positive lead on the negative cable.
Make sure that everything is off, shut and secured anything that could give you a false reading i.e. doors shut, trunk shut, hood light disconnected ect, ect...
Here is the hook up:
The amp meter will read high at first. When you connect the circuit you will hear a relay in the engine compartment click and the amp meter will jump up to around 8 amps, then immediately fall to 2 amps, then fall to .35 amps and then it will settle on .09 amps for approx 2 min. After the 2 minutes it should drop down to around 0.02 to 0.04 amps.
Here is the finial reading after the car went to sleep (approx 2 minutes from time to circuit connection to finial reading)
There are many things that can cause excessive current draw. Take the readings and let me know what you see.
Bill Curlee
Something is wrong. Your best bet is to use an AMP Meter and determine how much current the car draws when it is off and the electrical system goes to sleep. I went out to my 02 Z06 and took the readings just a few minutes ago!
Disconnect the negative battery cable, install an AMP Meter capable of reading at least 10 amps between the battery terminal and the cable.
Negative meter lead on the negative battery terminal and positive lead on the negative cable.
Make sure that everything is off, shut and secured anything that could give you a false reading i.e. doors shut, trunk shut, hood light disconnected ect, ect...
Here is the hook up:
The amp meter will read high at first. When you connect the circuit you will hear a relay in the engine compartment click and the amp meter will jump up to around 8 amps, then immediately fall to 2 amps, then fall to .35 amps and then it will settle on .09 amps for approx 2 min. After the 2 minutes it should drop down to around 0.02 to 0.04 amps.
Here is the finial reading after the car went to sleep (approx 2 minutes from time to circuit connection to finial reading)
There are many things that can cause excessive current draw. Take the readings and let me know what you see.
Bill Curlee
~ 4/sec, and just have not been able to pinpoint the source - need to lift the car to get below. Opened access to the BCM on passenger side kick panel - large multi wire bundle appears to have similar wire colors that run to the cd - in this harness can you tell me what color is a switched accessory wire? Any ideas what's causing the knocking and current draw in the lower left front? Appreciate your input, many thanks up-front!
RoyZ
Melting Slicks
Joined: Jun 2013
Posts: 3,473
Likes: 691
From: West Virginia
A good battery will start the car easily after 4-6 weeks. I have an 11 year old Sears Platinum (AGM) and it has no trouble starting the C5 every month or so during the winter if I am not using it - usually I do, but this winter it's been laid up waiting for it to get warm enough to do some needed work (detached, unheated garage).
So, either your battery is bad or you have a current drain for some reason. Multimeter time.
BTW, my OEM Delco failed (split) at a couple years old. The replacement Delco under warranty lasted about 8 years. The OEM battery in my wife's Subaru lasted 10 years - those kind of numbers should be your expectation these days.
So, either your battery is bad or you have a current drain for some reason. Multimeter time.
BTW, my OEM Delco failed (split) at a couple years old. The replacement Delco under warranty lasted about 8 years. The OEM battery in my wife's Subaru lasted 10 years - those kind of numbers should be your expectation these days.
Last edited by jackthelad; May 11, 2018 at 09:54 PM.
Melting Slicks
Joined: Jun 2013
Posts: 3,473
Likes: 691
From: West Virginia
After 2 days parked my 01 C5 draws down and will not start (battery test shows good) - ammeter shows a draw of ~ 2A, looking for 'live' ignition-off utilities and found the Bose cd changer trunk mtd (orange wire) was live with ignition off - ok that's one item I need to re-route to an ACC line. With the cd player unhooked I still have a draw of .62 to 1.10 (DVM integrates up/dwn ~every minute), while the DVM is hooked up there is a knocking (solenoid type noise) somewhere in the lower left front of the car, knock cycle is
~ 4/sec, and just have not been able to pinpoint the source - need to lift the car to get below. Opened access to the BCM on passenger side kick panel - large multi wire bundle appears to have similar wire colors that run to the cd - in this harness can you tell me what color is a switched accessory wire? Any ideas what's causing the knocking and current draw in the lower left front? Appreciate your input, many thanks up-front!
RoyZ
~ 4/sec, and just have not been able to pinpoint the source - need to lift the car to get below. Opened access to the BCM on passenger side kick panel - large multi wire bundle appears to have similar wire colors that run to the cd - in this harness can you tell me what color is a switched accessory wire? Any ideas what's causing the knocking and current draw in the lower left front? Appreciate your input, many thanks up-front!
RoyZ
There's a knocking sound from the ABS/AH unit when you reconnect a battery. Mine's an early (98) car so the unit is at the rear - they moved it to the front later. BUT you should only hear it for a very short time (10-20 seconds) after reconnecting your battery.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
After 2 days parked my 01 C5 draws down and will not start (battery test shows good) - ammeter shows a draw of ~ 2A, looking for 'live' ignition-off utilities and found the Bose cd changer trunk mtd (orange wire) was live with ignition off - ok that's one item I need to re-route to an ACC line. With the cd player unhooked I still have a draw of .62 to 1.10 (DVM integrates up/dwn ~every minute), while the DVM is hooked up there is a knocking (solenoid type noise) somewhere in the lower left front of the car, knock cycle is
~ 4/sec, and just have not been able to pinpoint the source - need to lift the car to get below. Opened access to the BCM on passenger side kick panel - large multi wire bundle appears to have similar wire colors that run to the cd - in this harness can you tell me what color is a switched accessory wire? Any ideas what's causing the knocking and current draw in the lower left front? Appreciate your input, many thanks up-front!
RoyZ
~ 4/sec, and just have not been able to pinpoint the source - need to lift the car to get below. Opened access to the BCM on passenger side kick panel - large multi wire bundle appears to have similar wire colors that run to the cd - in this harness can you tell me what color is a switched accessory wire? Any ideas what's causing the knocking and current draw in the lower left front? Appreciate your input, many thanks up-front!
RoyZ
The noise could be from the headlight motor. They attempt to Retorque to the SHUT position.
IF,,,,,,,,,,,,, The noise continues, the headlight control module could be the source of your draw.
Ive seen them go bad several times. The case seal on the back of the module dries out, splits and allows water/moisture to damage the module. They can also just go bad and never shut off. That causes the head light motor to continue to try to shut the head light door and always draw current....
See if you can isolate that module power.
Bill
Cruising
Joined: May 2011
Posts: 11
Likes: 0
Headlight Motor
Roy
The noise could be from the headlight motor. They attempt to Retorque to the SHUT position.
IF,,,,,,,,,,,,, The noise continues, the headlight control module could be the source of your draw.
Ive seen them go bad several times. The case seal on the back of the module dries out, splits and allows water/moisture to damage the module. They can also just go bad and never shut off. That causes the head light motor to continue to try to shut the head light door and always draw current....
See if you can isolate that module power.
Bill
The noise could be from the headlight motor. They attempt to Retorque to the SHUT position.
IF,,,,,,,,,,,,, The noise continues, the headlight control module could be the source of your draw.
Ive seen them go bad several times. The case seal on the back of the module dries out, splits and allows water/moisture to damage the module. They can also just go bad and never shut off. That causes the head light motor to continue to try to shut the head light door and always draw current....
See if you can isolate that module power.
Bill
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Drifting
Joined: Jan 2006
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From: Belhaven North Carolina
Cruise-In VIII Veteran
I also have a battery drain issue and I discovered that the lights in the DIC and HUD controls are not turning off, every other light in the car turns off as it should. So far my answer has been to install a quick disconnect at the battery.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Try to disconnect the battery for a few minutes and see if the BCM will reset its self.
You may have some corrosion on the BCM Board and it causing the BCM to turn on the lights in those modules. IF,, were my car, I would pull the BCM and use a magnifying glass and examine ALL areas of the circuit board traces, components, and connectors. Be careful, the board is ESD Sensitive.
Bill
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Racer
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From: Hattiesburg MS
Battery Drain
Maybe you can help me. When I store my car, after a few days a clicking noise starts. My conclusion is something is draining my battery any suggestions?
That is a bandaid repair and a PITA one to have.
Try to disconnect the battery for a few minutes and see if the BCM will reset its self.
You may have some corrosion on the BCM Board and it causing the BCM to turn on the lights in those modules. IF,, were my car, I would pull the BCM and use a magnifying glass and examine ALL areas of the circuit board traces, components, and connectors. Be careful, the board is ESD Sensitive.
Bill
Try to disconnect the battery for a few minutes and see if the BCM will reset its self.
You may have some corrosion on the BCM Board and it causing the BCM to turn on the lights in those modules. IF,, were my car, I would pull the BCM and use a magnifying glass and examine ALL areas of the circuit board traces, components, and connectors. Be careful, the board is ESD Sensitive.
Bill
Cruising
Joined: May 2011
Posts: 11
Likes: 0
Battery Drain
Battery drain also my problem and a few weeks ago Bill Curlee suggested checking the headlight motor - would get a knocking sound from the motor with a DVM connected in series across the battery lead.
I could feel the left headlight door was not fully closed flush by ~ 3/32" so i manually closed the headlight further using the manual crank, cycled the lights and now the knocking has stopped, (must be a position limit or torque sensor switch in the HL motor), the current draw decreased by greater than 1A leaving only the Bose CD changer live wired and that is drawing @ .3A current, but not sure how to re-wire this to an ACC leg.
Roy
I could feel the left headlight door was not fully closed flush by ~ 3/32" so i manually closed the headlight further using the manual crank, cycled the lights and now the knocking has stopped, (must be a position limit or torque sensor switch in the HL motor), the current draw decreased by greater than 1A leaving only the Bose CD changer live wired and that is drawing @ .3A current, but not sure how to re-wire this to an ACC leg.
Roy
