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Discussion Starter #1 (Edited)
Something is drawing power when the car is turned off, killing my battery anytime I let it sit for longer than 12 hours at a time. To troubleshoot I disconnected the ground from the battery and used a multimeter to measure the draw when turned off. It's 800mA which is obviously way above where it should be. I pulled fuses to find where the vampire component was located, and it runs through the AM2 fuse. I was able to deduce that the ignition is on that fuse so I disconnected it, but that didn't decrease the amps being drawn. I can't figure out what else might be on that fuse to keep up the guess and check, though.

Does anyone know what components all run through that fuse? Or have any broader ideas on the problem?

Thanks

Note: the Rav is a 3 door, 1996 model.
 

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Owner's manual (1999 Rav4) states the following:
AM2 5A fuse: Multiport fuel injection system/sequential multiport fuel injection system, SRS airbag system, seat belt pretensioners, starting system, discharge warning light.
 

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Discussion Starter #3
Owner's manual (1999 Rav4) states the following:
AM2 5A fuse: Multiport fuel injection system/sequential multiport fuel injection system, SRS airbag system, seat belt pretensioners, starting system, discharge warning light.
Hmm, mine is a 20A fuse but that at least gives me some more places to look. Thanks
 

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Hmm, mine is a 20A fuse but that at least gives me some more places to look. Thanks
It is hard to help you with this problem since you don't give the year of your Rav.

On my 99 if I had this problem, I would unplug the grey connector from the alternator and see if the current drop improves. But it is hard to guess what Toyota powered with the extra 15 amps you have.
 

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Discussion Starter #5
It is hard to help you with this problem since you don't give the year of your Rav.

On my 99 if I had this problem, I would unplug the grey connector from the alternator and see if the current drop improves. But it is hard to guess what Toyota powered with the extra 15 amps you have.
Ah, my bad. I was on my phone when I posted that and thought that it was in my profile box. I have a 3-door, 1996.
 

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On your 96 the charging system is part of AM2.
So I would still look at the alternator. Could be in the voltage regulator or a leaking diode.
 
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To troubleshoot I disconnected the ground from the battery and used a multimeter to measure the draw when turned off. It's 800mA which is obviously way above where it should be.
It is normal for the current to be higher when the battery is first connected. I understand that this is due to the fact that the computers perform initialization routines when first powered up. The AM2 fuse powers some of these computers.

The proper measurement can only be obtained about 20 minutes after reconnecting the battery in series with the ammeter. It is only if the current is still high after that period should you consider it a problem. In fact I would wait a full 30 minutes to see if the current drops, to avoid a wild goose chase.

I made this post some time ago which contains some links to support what I have said.
 

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The proper measurement can only be obtained about 20 minutes after reconnecting the battery in series with the ammeter. It is only if the current is still high after that period should you consider it a problem. In fact I would wait a full 30 minutes to see if the current drops, to avoid a wild goose chase.

I made this post some time ago which contains some links to support what I have said.
Good point, I keep forgetting these new cars have computers. :laugh
But if they take 20 minutes to wake up, what happens when you turn them off after 10 minutes of driving?

.
 

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But if they take 20 minutes to wake up, what happens when you turn them off after 10 minutes of driving? .
Since the computers in question receive constant battery power, regardless of the key setting, they would not be re-initialized when you started the engine, nor would they be powered down when you stop the engine after 10 minutes of driving. It's only after disconnecting the battery cable to insert the ammeter that the re-initialization would begin.
 

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Discussion Starter #10
It is normal for the current to be higher when the battery is first connected. I understand that this is due to the fact that the computers perform initialization routines when first powered up. The AM2 fuse powers some of these computers.

The proper measurement can only be obtained about 20 minutes after reconnecting the battery in series with the ammeter. It is only if the current is still high after that period should you consider it a problem. In fact I would wait a full 30 minutes to see if the current drops, to avoid a wild goose chase.

I made this post some time ago which contains some links to support what I have said.
This makes sense. To identify the problem I'll hook up the ammeter and let it sit for half an hour before pulling fuses. Will see what happens then. Thanks.
 
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