Alternator Drain Test Question
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Alternator Drain Test Question
Hello,
I have a current draw and running out of things to disconnect.
I wanted to check the alternator for current draw but have a question:
I know you have to run the Amp meter in series with post on back of alternator and + wire, but my question is: Does the battery need to be fully hooked up (both possitive and negative) to the car?
Or do I leave the negative post disconnected in the battery as if I was doing the normal drain test?
Thank you!
I have a current draw and running out of things to disconnect.
I wanted to check the alternator for current draw but have a question:
I know you have to run the Amp meter in series with post on back of alternator and + wire, but my question is: Does the battery need to be fully hooked up (both possitive and negative) to the car?
Or do I leave the negative post disconnected in the battery as if I was doing the normal drain test?
Thank you!
Tech Contributor
Joined: Jan 2007
Posts: 19,344
Likes: 1,123
From: Dyer, IN
Hello,
I have a current draw and running out of things to disconnect.
I wanted to check the alternator for current draw but have a question:
I know you have to run the Amp meter in series with post on back of alternator and + wire, but my question is: Does the battery need to be fully hooked up (both possitive and negative) to the car?
Or do I leave the negative post disconnected in the battery as if I was doing the normal drain test?
Thank you!
I have a current draw and running out of things to disconnect.
I wanted to check the alternator for current draw but have a question:
I know you have to run the Amp meter in series with post on back of alternator and + wire, but my question is: Does the battery need to be fully hooked up (both possitive and negative) to the car?
Or do I leave the negative post disconnected in the battery as if I was doing the normal drain test?
Thank you!
You never answered what the current draw is in the other thread, and if you are observing time for the BCM to go into sleep mode. It is not necessary to disconnect components, when you can just pull fuses for the circuits. It is also not necessary to test at the alternator, as you can leave the meter hooked up at the battery, allow the BCM to go into sleep mode, and disconnect the alternator to see if that has an impact.
Thread Starter
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My other thread is abotu my amp meter giving me 0 reading, now Im trying to find my current drain source.
I have disconnected the following and still getting a .40 A draw:
-Headlights Module
-Ignition Switch
-Amps from sound system
-Alternator
- Drivers seat (unplugged the whole thing and removed it)
I have checked and no lights in the car are on, even checked vanity mirrors and plud them off to make sure they werent staying on.
Im about to tear into the bose amp....if this is not it, any other ideas I should disconnect?
Thanks!
PS I am waiting at elast 10 min to make sure it goes into sleep mode.
I have disconnected the following and still getting a .40 A draw:
-Headlights Module
-Ignition Switch
-Amps from sound system
-Alternator
- Drivers seat (unplugged the whole thing and removed it)
I have checked and no lights in the car are on, even checked vanity mirrors and plud them off to make sure they werent staying on.
Im about to tear into the bose amp....if this is not it, any other ideas I should disconnect?
Thanks!
PS I am waiting at elast 10 min to make sure it goes into sleep mode.
Tech Contributor
Joined: Jan 2007
Posts: 19,344
Likes: 1,123
From: Dyer, IN
My other thread is abotu my amp meter giving me 0 reading, now Im trying to find my current drain source.
I have disconnected the following and still getting a .40 A draw:
-Headlights Module
-Ignition Switch
-Amps from sound system
-Alternator
- Drivers seat (unplugged the whole thing and removed it)
I have checked and no lights in the car are on, even checked vanity mirrors and plud them off to make sure they werent staying on.
Im about to tear into the bose amp....if this is not it, any other ideas I should disconnect?
Thanks!
PS I am waiting at elast 10 min to make sure it goes into sleep mode.
I have disconnected the following and still getting a .40 A draw:
-Headlights Module
-Ignition Switch
-Amps from sound system
-Alternator
- Drivers seat (unplugged the whole thing and removed it)
I have checked and no lights in the car are on, even checked vanity mirrors and plud them off to make sure they werent staying on.
Im about to tear into the bose amp....if this is not it, any other ideas I should disconnect?
Thanks!
PS I am waiting at elast 10 min to make sure it goes into sleep mode.
Good luck
http://forums.corvetteforum.com/c5-t...post1567522286
Thread Starter
Instructor
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Ok, again...you are doing things the hard way. Pulling out components, seats, etc.......is not necessary. You need only pull the appropriate fuses for circuits. So, I guess you have to do what makes sense to you. I'll step outta this one. Check out the thread below, starting with post #590......courtesy of a Bill Curlee...who is a very wise man......with much more patience than me......
Good luck
http://forums.corvetteforum.com/c5-t...post1567522286
Good luck
http://forums.corvetteforum.com/c5-t...post1567522286
Thread Starter
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OK, after taking my car apart like an idiot and still not finding the drain source, I took your advice and started pulling fuses; what a pain in the *** this was...
Anyway, I found that fuse #25 is the culprit! After removing this fuse the amps went down to .01-.02, perfect!
So now what in the world could be connected to fuse #25 that gives problems is my next question.
What can I do from here?
Any leads greatly appreciated!
Anyway, I found that fuse #25 is the culprit! After removing this fuse the amps went down to .01-.02, perfect!
So now what in the world could be connected to fuse #25 that gives problems is my next question.
What can I do from here?
Any leads greatly appreciated!
Tech Contributor
Joined: Jan 2007
Posts: 19,344
Likes: 1,123
From: Dyer, IN
OK, after taking my car apart like an idiot and still not finding the drain source, I took your advice and started pulling fuses; what a pain in the *** this was...
Anyway, I found that fuse #25 is the culprit! After removing this fuse the amps went down to .01-.02, perfect!
So now what in the world could be connected to fuse #25 that gives problems is my next question.
What can I do from here?
Any leads greatly appreciated!
Anyway, I found that fuse #25 is the culprit! After removing this fuse the amps went down to .01-.02, perfect!
So now what in the world could be connected to fuse #25 that gives problems is my next question.
What can I do from here?
Any leads greatly appreciated!
Last edited by lucky131969; Jan 28, 2010 at 05:23 PM.
Thread Starter
Instructor
Joined: Oct 2007
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Im definitely allowing the BCM to go into sleep mode and it keeps giving me a .40 A reading. The only thing that dropped it was when I took out fuse #25.
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Tech Contributor
Joined: Jan 2007
Posts: 19,344
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From: Dyer, IN
Ok so lets assume I disconnect the DIC/Cluster completely and the drain is still there? Would that mean my BCM is fried? Is there a way to test the BCM for leakage?
Im definitely allowing the BCM to go into sleep mode and it keeps giving me a .40 A reading. The only thing that dropped it was when I took out fuse #25.
Im definitely allowing the BCM to go into sleep mode and it keeps giving me a .40 A reading. The only thing that dropped it was when I took out fuse #25.
Obviously, removing the IPC would isolate it for sure, and only leave the BCM on circuit 1640. If it turns out that the BCM is the culprit, I would not declare it "fried" until you do some more research.
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Unfortunately, there are no internal schematics for the IPC, or BCM. The BCM has two fused sources for battery voltage(hot at all times), how the load is distributed is unknown. Under most circumstances, i would never suggested cutting a wire, but it all depends on how much you want to tear apart. Since the IPC and BCM battery feed wires are double staked at pin F8, of connector C1 of the fuse box, the only way to isolate the IPC would be to cut the orange wire to the IPC. You would have to be sure you are cutting the right one, because both wires are orange, so you would have to trace the wire back to the BCM, and make sure you don't cut that one. Again, it's not something I advocate.
Obviously, removing the IPC would isolate it for sure, and only leave the BCM on circuit 1640. If it turns out that the BCM is the culprit, I would not declare it "fried" until you do some more research.
Obviously, removing the IPC would isolate it for sure, and only leave the BCM on circuit 1640. If it turns out that the BCM is the culprit, I would not declare it "fried" until you do some more research.
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Its not small...put it this way...I turned the car on in the morning, went to work, parked it for about 4 hours, was heading to lunch and the battery was dead enough not to turn car over. THats how fast it drained it. And this is a new battery jsut replaced thinking it was the battery.
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Ok so I pulled out the complete cluster and disconnected it, just to be sure that wasnt the problem...but still getting same reading!!!!!!! CRAP .40 A draw at sleep.
What else can this be? I really hope is not my BCM...dunno what else to do!
What else can this be? I really hope is not my BCM...dunno what else to do!
Tech Contributor
Joined: Jan 2007
Posts: 19,344
Likes: 1,123
From: Dyer, IN
I've looked at a few more things. I'll PM you my number, if you want my help. As far as I know, Bill is traveling right now for work.
