Resting current draw on battery

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greiswig

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I seem to have an issue. If I'm reading my multimeter correctly, I've got around .6 amps of current draw from the main/starting battery with the vehicle sitting there doing nothing. That seems like a lot!

This is related to the other thread I posted about whether there is an actual "accessory" position. If I get in the vehicle and listen to the stereo without running the engine for any length of time, I get the "Battery low. Start engine" warning. That doesn't seem right either.

So I disconnected the battery negative, then put my Fluke 29 between the negative post and the negative cable. The Fluke reads 6.xx on the 10 Amp scale. But I think that actually is autoscaling, and it's probably reading 10ths of an amp.

I left it hooked up this way for 5 minutes or so, thinking that maybe something needed to shut down after hooking up the battery again. But it stayed pretty steady at that current rate.

Any ideas? This can't be normal. Most battery manufacturers tell you to keep parasitic draw down below 40mA.
 

jlglr4

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So many systems on these cars, that I’m not even sure 5 minutes would be enough to know it’s shut down. But, the other source of a parasitic draw can be a bad alternator diode.
 

jlglr4

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One other thought - when you’re waiting for your car to shut down, might want to have your key far away from the car. Not sure about these LRs, but my wifes volvo stays quite alive as long as the key is in range.
 

f1racer328

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In the summertime even after locking my car I can hear a cooling fan running towards the back of the car.

Only happens when it’s 105+ out usually, but there’s a lot going on.
 

greiswig

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Great info, all. I’ll do some more testing and report back for posteriors...er, posterity’s sake.
 

AdventureTim

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My LR4 draws 6-7 amps when in a "wake" state (i.e. just unlocked and the door opened) -- definitely more than I would have expected. When I lock the car, it takes a few minutes to drop to ~2 amps, and then after about 15 mins drops to < 0.5 amp.
 

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