Need Help Chasing a Battery Drain
10-02-2009, 10:14 AM
#16
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I had a maddening drain in my car, and it turned out to be a combination of a sticking passenger window switch and two relays that were reversed in the CE panel - the incorrect relay for the electric windows caused the circuit to stay live even after the key was out, and the passenger window switch was sticking in the UP position due to friction from the center console trim, draining my battery once a week. That problem only drew about half an amp - far short of your drain. I would definitely focus my attention on major shorts...
10-02-2009, 08:35 PM
#17
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OK so with everything disconnected you see basically no current - thats a start.
Your measurement method seems OK (you are using the seperate 10A shunt connector right)
1) Reconnect the starter main terminal (to the battery connector only) - measure?
2) Reconnect the alternator connector to the starter, with the jump post connectors disconnected - measure?
3) Reconnect only the big cable from the alternator to the jump post - measure?
4) Reconnect all the connectors to the jump post w/ all fuses out - measure ?
BTW folks ~2A is not a huge short... its ~20W equivalent a couple of interior light bulbs or a few marker lamp bulbs. It would probably not cause any damage to any wiring in the car..
I do think you should suspect the strange dash behaviour - this sounds like agrounding problem - I'd check the pod grounds particularly - maybe they were not reconnecetd properly after some service.
Generally the interior lights are good things to check - however with all the fuses pulled that should not be a problem... as noted suspect any aftermarket wiring - people do the wierdest things... presumably accidentally...?!?!
Try removing the defoster relay - another common cause.
Alan
Your measurement method seems OK (you are using the seperate 10A shunt connector right)
1) Reconnect the starter main terminal (to the battery connector only) - measure?
2) Reconnect the alternator connector to the starter, with the jump post connectors disconnected - measure?
3) Reconnect only the big cable from the alternator to the jump post - measure?
4) Reconnect all the connectors to the jump post w/ all fuses out - measure ?
BTW folks ~2A is not a huge short... its ~20W equivalent a couple of interior light bulbs or a few marker lamp bulbs. It would probably not cause any damage to any wiring in the car..
I do think you should suspect the strange dash behaviour - this sounds like agrounding problem - I'd check the pod grounds particularly - maybe they were not reconnecetd properly after some service.
Generally the interior lights are good things to check - however with all the fuses pulled that should not be a problem... as noted suspect any aftermarket wiring - people do the wierdest things... presumably accidentally...?!?!
Try removing the defoster relay - another common cause.
Alan
10-02-2009, 10:14 PM
#18
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Most of the electrical circuits in the car are powered thru the wires that run from the jump start connection to the Central Electrical Panel.
About the best that you can do from where you are is to see whether the drain is in the alternator or not.
Connecting the lines in the 14-pin connector will do nothing if none of the electrical circuits are powered.
If the drain reappears when you reconnect the main power feed lines, all you know is that the drain is in the car somewhere.
I would start by checking the alternator. I would then connect everything back up and make sure that the drain is still there. I would then disconnect each of the plugs at the bottom of the panel one at a time. When the drain went away, you have only a few circuits to check.
About the best that you can do from where you are is to see whether the drain is in the alternator or not.
Connecting the lines in the 14-pin connector will do nothing if none of the electrical circuits are powered.
If the drain reappears when you reconnect the main power feed lines, all you know is that the drain is in the car somewhere.
I would start by checking the alternator. I would then connect everything back up and make sure that the drain is still there. I would then disconnect each of the plugs at the bottom of the panel one at a time. When the drain went away, you have only a few circuits to check.
10-11-2009, 12:31 AM
#19
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PROGRESS!!
It's in the starter somewhere! After an absolutely horrible week filled with overtime, more overtime, and then having my house broken in to I finally found some time to work on the car (you know, after the cops had to come by and CSI my place - thankfully the bastard thieves must have been young kids, took electronics, didn't touch the tools) Anyways,
The drain is in the starter, or the wires leading to it. I have the alternator, jump post, and the 14-pin connector hooked up, no drain, plug in the starter, boom there it is. So, it is somewhere in there. Now I don't know the extent of the wiring that this could mean is effected, or if it is the alternator itself, so I'm wondering if you guys could give me some help on where to go from here. Do I try swapping it with a known good starter, and if that fixes it, hooray, and if it doesn't start following the wires?
Still a ways to go, but I'm that much closer.
It's in the starter somewhere! After an absolutely horrible week filled with overtime, more overtime, and then having my house broken in to I finally found some time to work on the car (you know, after the cops had to come by and CSI my place - thankfully the bastard thieves must have been young kids, took electronics, didn't touch the tools) Anyways,
The drain is in the starter, or the wires leading to it. I have the alternator, jump post, and the 14-pin connector hooked up, no drain, plug in the starter, boom there it is. So, it is somewhere in there. Now I don't know the extent of the wiring that this could mean is effected, or if it is the alternator itself, so I'm wondering if you guys could give me some help on where to go from here. Do I try swapping it with a known good starter, and if that fixes it, hooray, and if it doesn't start following the wires?
Still a ways to go, but I'm that much closer.
10-11-2009, 12:43 AM
#20
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I'd take the starter to a local rebuilder and have them check it over. Don't go to Autozone, etc. because even if they have a test rig, most employees don't know much more than what button to push.
10-19-2009, 12:46 PM
#21
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One quick question though - the black and red wires on the starter were screwed in to the same post - I searched on this and it appears that is normal. Since I've got the starter off currently, if I get under there and bolt those two wires together, and then plug the battery back up, can I do this to test if there is a short in the wiring as opposed to my starter itself, or will that be a bad test?
10-19-2009, 01:45 PM
#22
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I think I have a different color code -- one yellow wire in there IIRC -- but that should be a good test. just make sure it doesn't touch the chassis! You might want to wrap some electrical tape around it to be sure.
10-19-2009, 02:57 PM
#23
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Yes, it is normal for the large black cable (main feed cable from the battery to the car) and the medium-sized red cable or cables (main feed to/from the alternator to the battery and car) to be on the same major terminal.
If you didn't have this connected, you didn't have the alternator connected...
If you connect these two cables, hook up the battery and then have a current drain, the problem might well be a shorted output diode in the alternator.
If you didn't have this connected, you didn't have the alternator connected...
If you connect these two cables, hook up the battery and then have a current drain, the problem might well be a shorted output diode in the alternator.
10-19-2009, 03:21 PM
#24
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Yes, it is normal for the large black cable (main feed cable from the battery to the car) and the medium-sized red cable or cables (main feed to/from the alternator to the battery and car) to be on the same major terminal.
If you didn't have this connected, you didn't have the alternator connected...
If you connect these two cables, hook up the battery and then have a current drain, the problem might well be a shorted output diode in the alternator.
If you didn't have this connected, you didn't have the alternator connected...
If you connect these two cables, hook up the battery and then have a current drain, the problem might well be a shorted output diode in the alternator.
also, earlier in the thread I had the starter hooked up, but took the big red wire off the alternator and the drain shot the hell up, which made me not think it was the alt. Thoughts?
10-20-2009, 09:47 PM
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Well damnit, I felt so sure and now I've taken a step back, at least this happened before I shelled out the cash for a new starter.
With the starter off, but the red and black wire from the starter connected, the drain persist. With those wires connecting, and the hot wire off the alternator, the drain persists. With the hot wire off the alternator, and the jump post off (which, by the way, I'm undoing the jump post from the mount with the two screws under the cover, is that correct or is there another place I need to disconnect this to isolate it?) it persists. When I seperate the two hot wires from the starter, it goes away. So what I know is that as long as those two wires are connected, I will have a drain. What does this tell me?
Thank you again for all of your help, it is greatly appreciated.
With the starter off, but the red and black wire from the starter connected, the drain persist. With those wires connecting, and the hot wire off the alternator, the drain persists. With the hot wire off the alternator, and the jump post off (which, by the way, I'm undoing the jump post from the mount with the two screws under the cover, is that correct or is there another place I need to disconnect this to isolate it?) it persists. When I seperate the two hot wires from the starter, it goes away. So what I know is that as long as those two wires are connected, I will have a drain. What does this tell me?
Thank you again for all of your help, it is greatly appreciated.
10-20-2009, 10:34 PM
#27
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to disconnect the hot post get an 11mm wrench and remove the stud, this connects the alternator to the CE panel.
Leave the 2 screws that hold the hot post to chassis alone.
You may already be doing this
Leave the 2 screws that hold the hot post to chassis alone.
You may already be doing this
10-21-2009, 11:06 AM
#28
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*faceplam*
well, I wasn't doing that right, but I've seen the error of my ways. Going to go home and get this sorted again. I'm having trouble visualizing how everything is interconnecting. The Starter has a hot wire directly from the battery, then there is another heavy gauge wire that goes to the jump post, alternator and starter?
The wire from the alternator to the starter, is that a direct wire, or does it go through the jump post first? I'm trying to understand the current flow so I can see what is downstream from what to hopefully figure this out, but alas I have no wiring diagrams
well, I wasn't doing that right, but I've seen the error of my ways. Going to go home and get this sorted again. I'm having trouble visualizing how everything is interconnecting. The Starter has a hot wire directly from the battery, then there is another heavy gauge wire that goes to the jump post, alternator and starter?
The wire from the alternator to the starter, is that a direct wire, or does it go through the jump post first? I'm trying to understand the current flow so I can see what is downstream from what to hopefully figure this out, but alas I have no wiring diagrams
10-21-2009, 11:12 AM
#29
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I keep telling you:
Sequentially:
battery -> starter ->alternator -> jump post -> top of the fuse panel
exactly like this - no visualization required
Take the alternator in for testing - almost certainly one of the diodes is leaking (as long as the test results your gave were accurate).
If you are going to do any (electrical etc) work on the car you wll need the factory workshop
manuals... you won't get anywhere without them - so get them now (at least on CD) or plan to pay someone else to do the work...
Even with them you will still have tons of questions... and you may not even understand the wiring diagrams at first... more questions...
Alan
Sequentially:
battery -> starter ->alternator -> jump post -> top of the fuse panel
exactly like this - no visualization required
Take the alternator in for testing - almost certainly one of the diodes is leaking (as long as the test results your gave were accurate).
If you are going to do any (electrical etc) work on the car you wll need the factory workshop
manuals... you won't get anywhere without them - so get them now (at least on CD) or plan to pay someone else to do the work...
Even with them you will still have tons of questions... and you may not even understand the wiring diagrams at first... more questions...
Alan
10-29-2009, 12:34 AM
#30
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Update - I hate this damn thing.
So here's where I have it.
1. Starter removed, but the two wires that go to it are connected, and electrical taped together
2. Both wires on the alternator are disconnected
3. The jump post is removed, the wires disconnected
4. The 14-pin connector to the engine is removed
5. there were a couple large wires that came before the jump post, two went in to a couple small, green wires, one with a yellow stripe. these went to to pins at the front of the intake manifold.
5. There was a charred looking two-pin connector directly below these that also had a wire from the same group with the jump post leading to it. This is once again on the top of the engine near the front of the intake manifold, I removed them
6. Every single fuse in the passenger footwell is removed
I still have a 2.2-2.4amp drain with all of this done.
If I un-tape the two wires connected where the starter used to be, the drain goes away.
What I have not done, and am about to do, is pull every relay and/or all the plugs underneath the relays and see if the drain disappears with those removed. After that, I have no clue and once again humbly ask you rennlisters to send me in a direction.
FWIW, I have an amp-clamp style multimeter that I picked up at HF (junk, but cheap junk that works if only for a short while I know) yet I'm not terribly knowledgeable about using the clamp portion of it. I hear they can be useful for finding these kinds of drains, if yall have some advice there, I'm all ears.
So here's where I have it.
1. Starter removed, but the two wires that go to it are connected, and electrical taped together
2. Both wires on the alternator are disconnected
3. The jump post is removed, the wires disconnected
4. The 14-pin connector to the engine is removed
5. there were a couple large wires that came before the jump post, two went in to a couple small, green wires, one with a yellow stripe. these went to to pins at the front of the intake manifold.
5. There was a charred looking two-pin connector directly below these that also had a wire from the same group with the jump post leading to it. This is once again on the top of the engine near the front of the intake manifold, I removed them
6. Every single fuse in the passenger footwell is removed
I still have a 2.2-2.4amp drain with all of this done.
If I un-tape the two wires connected where the starter used to be, the drain goes away.
What I have not done, and am about to do, is pull every relay and/or all the plugs underneath the relays and see if the drain disappears with those removed. After that, I have no clue and once again humbly ask you rennlisters to send me in a direction.
FWIW, I have an amp-clamp style multimeter that I picked up at HF (junk, but cheap junk that works if only for a short while I know) yet I'm not terribly knowledgeable about using the clamp portion of it. I hear they can be useful for finding these kinds of drains, if yall have some advice there, I'm all ears.