Battery draining issue
Thread Starter
Le Mans Master
Joined: Jun 2003
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From: Norman, OK
St. Jude '03-'04-'05-'06-'07-'08-'09
Battery draining issue
It just started and I can't seem to find it. When I connect and disconnect the battery I can feel and hear something making a clunking sound. I have removed the fuses from both light motors and disconnected ther weatherpack connectors and it still makes the noise. I can actually feel it when I touch the side of the light motor. Any idea what else can be inside there, this is on the pass side. Thanks
Pro
Joined: Jan 2004
Posts: 678
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From: Alpena Michigan
What you're hearing is most likely the headlight module. It's located on the right side just behind the headlight opening and has two plugs connected to it. It controls the up/down of your headlights. Mine clicks when I connect and disconnect the battery. Just went through the same ordeal with the battery draining, ended up being a defective 1 year old Delco battery. It would only take a surface charge and would go dead in about 24 hours. If you haven't done/changed anything on your car that might cause the problem I would put a known good battery in and see if it goes dead. The C5 has some parasitic drains normally, also they're not like the older 70's 80's cars where you could just hook a voltmeter in series on the neg battery cable and neg post and if it showed battery voltage (12 volts or more) you knew you had a short. Be careful diagnosing as the electrical systems/modules are very sensitive to current surges, sparks, ect... Good luck finding your problem.
Thread Starter
Le Mans Master
Joined: Jun 2003
Posts: 5,240
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From: Norman, OK
St. Jude '03-'04-'05-'06-'07-'08-'09
What you're hearing is most likely the headlight module. It's located on the right side just behind the headlight opening and has two plugs connected to it. It controls the up/down of your headlights. Mine clicks when I connect and disconnect the battery. Just went through the same ordeal with the battery draining, ended up being a defective 1 year old Delco battery. It would only take a surface charge and would go dead in about 24 hours. If you haven't done/changed anything on your car that might cause the problem I would put a known good battery in and see if it goes dead. The C5 has some parasitic drains normally, also they're not like the older 70's 80's cars where you could just hook a voltmeter in series on the neg battery cable and neg post and if it showed battery voltage (12 volts or more) you knew you had a short. Be careful diagnosing as the electrical systems/modules are very sensitive to current surges, sparks, ect... Good luck finding your problem.
Le Mans Master
Joined: Aug 2005
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From: DP(oh you know where) IL
St. Jude Donor '06
When you hear that clicking noise, its just some of the relays that are opening or closing. Normal noises there when you connect and disconnect the battery. Check some of your grounds. Bill Curlee has some threads about finding bad grounds.
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
It just started and I can't seem to find it. When I connect and disconnect the battery I can feel and hear something making a clunking sound. I have removed the fuses from both light motors and disconnected ther weatherpack connectors and it still makes the noise. I can actually feel it when I touch the side of the light motor. Any idea what else can be inside there, this is on the pass side. Thanks
There are NUMEROUS post on current draw and how to troubleshoot and correcting this issue. I have posted twice this month on this very topic. Look under post from me or search C5 Tech under CURRENT DRAW
Bill Curlee
Thread Starter
Le Mans Master
Joined: Jun 2003
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From: Norman, OK
St. Jude '03-'04-'05-'06-'07-'08-'09
Pro
Joined: Jan 2004
Posts: 678
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From: Alpena Michigan
Just a shot in the dark here but have you installed anything or made any changes to the car lately? Exhaust work? Wire melted on exhaust? You can unplug the headlight module to eliminate it if it sounds real loud. Mine just makes an audible click when hooking up the battery. Sorry not much help here!
Thread Starter
Le Mans Master
Joined: Jun 2003
Posts: 5,240
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From: Norman, OK
St. Jude '03-'04-'05-'06-'07-'08-'09
Just a shot in the dark here but have you installed anything or made any changes to the car lately? Exhaust work? Wire melted on exhaust? You can unplug the headlight module to eliminate it if it sounds real loud. Mine just makes an audible click when hooking up the battery. Sorry not much help here!
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Pro
Joined: Jan 2004
Posts: 678
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From: Alpena Michigan
No changes of any kind. I did the search and will try some of those things tomorrow but I really don't think the problem is a bad ground. There is enough draw to melt a 10 gage wire when placed inbetween the battery (neg) and the neg connector. I pulls down the battery overnight.
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
HOLY ****SKIES! Thats a LOT of amps in the OFF/SLEEP MODE!!!!
You need to start troubleshooting by deviding the two fuse boxes. The B+ connection on the engine fuse box has TWO wires.
One is the battery wire and the other is the wire that comes from the passengers fuse box. Remove the wire that feeds through to the passengers fuse box.
Hook that wire back up and see if you have the same current draw.
WOW!
BC
You will need to
You need to start troubleshooting by deviding the two fuse boxes. The B+ connection on the engine fuse box has TWO wires. One is the battery wire and the other is the wire that comes from the passengers fuse box. Remove the wire that feeds through to the passengers fuse box.
Hook that wire back up and see if you have the same current draw.
WOW!
BC
You will need to
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
With that kind of draw it sounds like a short of some kind. Another thing to try is to unplug the alternator and also unhook the heavy red wire from it. That would eliminate the alternator from being the cause of a short. You can take the nut off the connection on the under hood fuse box and separate the connections there and see if that will help you isolate it.
BC
Thread Starter
Le Mans Master
Joined: Jun 2003
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From: Norman, OK
St. Jude '03-'04-'05-'06-'07-'08-'09
Thank you Sooooo much, now it seems we are going to get somewhere. I have disconnected the battery for the night and will try that in the morning.
Thread Starter
Le Mans Master
Joined: Jun 2003
Posts: 5,240
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From: Norman, OK
St. Jude '03-'04-'05-'06-'07-'08-'09
HOLY ****SKIES! Thats a LOT of amps in the OFF/SLEEP MODE!!!! You need to start troubleshooting by deviding the two fuse boxes. The B+ connection on the engine fuse box has TWO wires.
One is the battery wire and the other is the wire that comes from the passengers fuse box. Remove the wire that feeds through to the passengers fuse box.
Hook that wire back up and see if you have the same current draw.
WOW!
BC
You will need to
You need to start troubleshooting by deviding the two fuse boxes. The B+ connection on the engine fuse box has TWO wires. One is the battery wire and the other is the wire that comes from the passengers fuse box. Remove the wire that feeds through to the passengers fuse box.
Hook that wire back up and see if you have the same current draw.
WOW!
BC
You will need to
Last edited by mrw173; May 1, 2007 at 10:50 AM.
Thread Starter
Le Mans Master
Joined: Jun 2003
Posts: 5,240
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From: Norman, OK
St. Jude '03-'04-'05-'06-'07-'08-'09
I have disconnected the inside fuse box from the B+ connector and it is definatelly on the inside of the car as I get a very low readung with it removed. I have disconnected both leads from the B+ post and connected them together and the problem is back. I will start pulling fuses from inside the car.
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
What ever is comsuming that much current has to be H O T!!! There are only a few things that I can think of that would cause that much draw:
The passengers or drivers seat motors being stuck on. Check the multifunction switch and see if it is centered.
The rear window defroster.
The alternator diodes being bad and drawing current when the engine is OFF
The headlight control module. It under the passengers headlight on the frame header bar.
Feel all of these and see if antof them are HOT.
Bill
There are only a few things that I can think of that would cause that much draw:The passengers or drivers seat motors being stuck on. Check the multifunction switch and see if it is centered.
The rear window defroster.
The alternator diodes being bad and drawing current when the engine is OFF
The headlight control module. It under the passengers headlight on the frame header bar.
Feel all of these and see if antof them are HOT.
Bill
Thread Starter
Le Mans Master
Joined: Jun 2003
Posts: 5,240
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From: Norman, OK
St. Jude '03-'04-'05-'06-'07-'08-'09
What ever is comsuming that much current has to be H O T!!! There are only a few things that I can think of that would cause that much draw:
The headlight control module. It under the passengers headlight on the frame header bar.
Feel all of these and see if antof them are HOT.
Bill
There are only a few things that I can think of that would cause that much draw:The headlight control module. It under the passengers headlight on the frame header bar.
Feel all of these and see if antof them are HOT.
Bill
I bet you are right here!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
This is where I am hearing noise.
How can I get at this module though, it looks to be inside an area that is inaccessible.
Pro
Joined: Jan 2004
Posts: 678
Likes: 2
From: Alpena Michigan
If you have small hands you can go in from the top on the right side (standing in front of the car facing the light) of the light (with the light in the up position) to unplug the module. It has two plugs going to it. Unhook the battery before doing this so the light doesn't close when you unplug it with your hand in there! Might give you a little more room with the plastic headlight surround removed also.
Might give you a little more room with the plastic headlight surround removed also.
Drifting
Joined: Jan 2005
Posts: 1,342
Likes: 3
From: Arlington TX
I'm having this same issue.. I'm definately 
Mine is slow.. I thought it was my battery so I replaced it with an optima red top, but the drain is still there. I *thought* it was an interior light, so I readjusted the glove box which did have a light on, and then I flipped the breaker on my stereo system.. I thought the cap was doing it.. but it's still there... very slow drain.. not sure what the hell it is.
Mine is slow.. I thought it was my battery so I replaced it with an optima red top, but the drain is still there. I *thought* it was an interior light, so I readjusted the glove box which did have a light on, and then I flipped the breaker on my stereo system.. I thought the cap was doing it.. but it's still there... very slow drain.. not sure what the hell it is.