Parasitic battery draw
Thread Starter
Instructor
Joined: Mar 2008
Posts: 184
Likes: 17
Parasitic battery draw
Trying to troubleshoot a parasitic battery draw.
I have a 1.7 amp draw when I initially apply the meter (set at 20 amps) leads to the battery terminal. After 30 seconds it drops to ~0.9 amp draw.
Pulled all the fuses in the engine bay, no difference.
Unplugged the alternator, no difference.
Lower passenger side fuse box, pulled Fan blower fuse and the draw dropped to ~0.6 amp, still high. Haven't finished pulling all the fuses yet.
Is there a way to disable the interior courtesy lamps when I open the door? I've been disconnecting the meter, pulling the fuse, closing the door, reconnect meter to avoid the amp spike from the courtesy lamp draw.
Thanks
I have a 1.7 amp draw when I initially apply the meter (set at 20 amps) leads to the battery terminal. After 30 seconds it drops to ~0.9 amp draw.
Pulled all the fuses in the engine bay, no difference.
Unplugged the alternator, no difference.
Lower passenger side fuse box, pulled Fan blower fuse and the draw dropped to ~0.6 amp, still high. Haven't finished pulling all the fuses yet.
Is there a way to disable the interior courtesy lamps when I open the door? I've been disconnecting the meter, pulling the fuse, closing the door, reconnect meter to avoid the amp spike from the courtesy lamp draw.
Thanks
Drifting
Joined: Mar 2010
Posts: 1,628
Likes: 15
From: Seattle WA
I don't think the courtesy lamps will spike 20 amps through your meter. However, you could just pull the courtesy lamp fuse, should be minifuse 29 unless that changes over the years (the better electrical gurus will chime in and correct me).
EDIT: You may want to pull microrelay 42 instead, as pulling fuse 29 will drop other loads as well and that might not be what you want when you're trying to track the draw.
EDIT: You may want to pull microrelay 42 instead, as pulling fuse 29 will drop other loads as well and that might not be what you want when you're trying to track the draw.
Last edited by Trios; Jun 30, 2015 at 01:58 PM.
Thread Starter
Instructor
Joined: Mar 2008
Posts: 184
Likes: 17
I don't think the courtesy lamps will spike 20 amps through your meter. However, you could just pull the courtesy lamp fuse, should be minifuse 29 unless that changes over the years (the better electrical gurus will chime in and correct me).
EDIT: You may want to pull microrelay 42 instead, as pulling fuse 29 will drop other loads as well and that might not be what you want when you're trying to track the draw.
EDIT: You may want to pull microrelay 42 instead, as pulling fuse 29 will drop other loads as well and that might not be what you want when you're trying to track the draw.
The meter is set to handle up to 20 amps.
Pulled micro relay 42 and then fuse 29, lights don't go on but still got the 4-5 amp spike.
Picture of fuse layout, any other suggestions?
Drifting
Joined: Mar 2010
Posts: 1,628
Likes: 15
From: Seattle WA
I thought you were asking how to shut off the lamps so you could set up the meter and then get in the car to start pulling more fuses. So, do that. Set up the meter, put it on the windscreen where you can see it from inside the car, get in, close the door, wait for current to drop (can take a few minutes) and then start pulling fuses to see which one is your major current draw.
Team Owner
Joined: May 2001
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Couldn't you just temporarily remove both of the the B+ cables from the U/H fuse box, and re-connect them together to each other with a bolt/nut, then disconnect the B+ cable where it connects to the interior fuse box, and insert your DVOM in series at that location?
That way you've isolated the U/H fuse box plus have the DVOM inside the car where you're working.
That way you've isolated the U/H fuse box plus have the DVOM inside the car where you're working.
Thread Starter
Instructor
Joined: Mar 2008
Posts: 184
Likes: 17
I can't shut the door and be able to reach underneath to pull fuses 
What I didn't try was pulling the fuse/relay and wait a few minutes to see if the 4-5 amp spike drops. I think the open door shouldn't matter at this point unless their is a Door Control Module (DCM) sending signal to the Body Control Module (BCM)....I'll try it out
What I didn't try was pulling the fuse/relay and wait a few minutes to see if the 4-5 amp spike drops. I think the open door shouldn't matter at this point unless their is a Door Control Module (DCM) sending signal to the Body Control Module (BCM)....I'll try it out
Thread Starter
Instructor
Joined: Mar 2008
Posts: 184
Likes: 17
Couldn't you just temporarily remove both of the the B+ cables from the U/H fuse box, and re-connect them together to each other with a bolt/nut, then disconnect the B+ cable where it connects to the interior fuse box, and insert your DVOM in series at that location?
That way you've isolated the U/H fuse box plus have the DVOM inside the car where you're working.
That way you've isolated the U/H fuse box plus have the DVOM inside the car where you're working.
It reduces the risk of shorting something out.
Drifting
Joined: Mar 2010
Posts: 1,628
Likes: 15
From: Seattle WA
Sorry about the suggestion to close the door, then. I'm a small guy, so I didn't really think about that being a problem. I don't know how to continue troubleshooting without closing the door, though; I'm certain there's lots of things the BCM does when the door is open other than just turn on the lights, and it'll affect your readings.
Maybe ask a smaller friend or family member to crawl in there head first and close the door on them?
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Le Mans Master
Joined: Feb 2004
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From: York PA
I use a screwdriver to close the door latches in the door, the car thinks the doors are closed.
Don't forgot to undo the latch before closing.
Check the car in total darkness, could be an interior light not turning off
Don't forgot to undo the latch before closing.
Check the car in total darkness, could be an interior light not turning off
Team Owner
Joined: May 2001
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Nah, this won't work with the negative side. He's talking about removing the power source from the fuse block and running the underhood fuse block (and only the underhood fuse block) out of your DMM. You've already isolated that the problem isn't in the underhood fuse block, so I don't know what the purpose would be.
Since the OP is too big to work inside the car without the door being open it may be a moot point, so........