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Discussion Starter #1
1:
So pardon my ignorance, but when multi meter is set to 5A, and I get a reading of .19, is that 190 milliamps?


If I pull fuse #15 (GEM, PCM, Stop Lamp, memory, abs, cluster, shift interlock, etc...), my draw goes down to .02 (is that 20 milliamps?).

2:
I read 50 milliamps is acceptable. Is that true?


With meter attached, I let truck sit for 45 minutes to "go to sleep", and reading drops from.19 to .02.

If I let truck sit for 4 days, batteries are too weak to start engine.

I load tested the batteries at autozone, and they came out fine. They had a pretty cool tester that scanned the VIN and knew I had 2 batteries and 2 alternators.

As a test, I disconnected both batteries for 4 days last week, and when I hooked them back up, truck fired right up. So that tells me bats are good.

I wonder if I have an intermittent draw that only shows when conditions are right.

3:
Where do I go from here?


On a side note, I did have a leaking windshield that needed an new windshield frame welded in.
All the metal under the dash is rusty, GEM looked fine when I took it apart.
I did put a sheet of plastic over top of the gem and fuse box in case of future leaks.
Stop lamp switch harness was full of water when I took it apart. Unhooking harness didn't stop battery draw.
 

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Yes, .19 amps is 190 milliamps.
You should get less than 50 mA when the PCM and other modules are asleep. I think that if you've pulled the fuse for the PCM & GEM, you should get zero amp draw.
You windshield leak could be causing a voltage draw as well. But those are a bugger to track down.

Have you checked the alternator? If diodes are bad, they will discharge the batteries thru the alternator. Where are you measuring amp draw? At the battery?
 

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Discussion Starter #3
Yes, .19 amps is 190 milliamps.
You should get less than 50 mA when the PCM and other modules are asleep. I think that if you've pulled the fuse for the PCM & GEM, you should get zero amp draw.
You windshield leak could be causing a voltage draw as well. But those are a bugger to track down.

Have you checked the alternator? If diodes are bad, they will discharge the batteries thru the alternator. Where are you measuring amp draw? At the battery?
Yes, measuring amp draw between neg post and terminal.

I pulled big wire Off back of top alternator, still had draw.
I tried to do same with bottom alternator, but i couldn't see the wires, much less get a hand in there.

How the heck do they change those? Pull the radiator???
 

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How the heck do they change those? Pull the radiator???
Don't know. I haven't tried. Maybe from below and behind the radiator? At least you're not working on a van.

You'll need to pull individual fuses to find out what circuit it's on. Be aware that some fuses feed others, so you need to pull the most downstream fuses first to narrow it down.
 
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