Electrical Problem?

Maintenance/Repairs
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1

I have an old Toyota Camry 4 cylinder. When I leave the car parked for more than 2 days the battery gets totally drained. I checked lights, fuses, interior lights, ignition switch, etc. to make sure that nothing is left ?on?, yet the battery gets drained. It seems that there is something left ‘on’ that is slowly using the battery while the car is parked.

Does someone know what the problem is and/or suggest what I need to check so I know what to fix?. Thanks.

2

With everything shut off, engine NOT running disconnect the battery negative cable and insert an ammeter between the cable and the battery. If the meter reads under about 50 milliamps of an amp you probably have a failing battery. If it reads over 50 milliamps you have a parasitic drain. Remove fuses one at a time until the meter reading drops, this will tell you which fuse is feeding the drain. Once you know which fused circuit the drain is on you’ll have to track each wire or device and unplug them one at a time until you find the problem.

3

How old is the battery? It may just not be able to hold a charge anymore. When you turn the car off do you hear anything? I once had a VW GTI that left something running when I turned the engine off (I believe it was something to do with the fuel system) and would drain the battery.

4

Can someone with electrical knowledge indicate where the drain might come from?
The basic and obvious things (battery (one month old), fuses, cables, lights, etc. have been checked.
JayWB: The fuse test suggested has already been done without any drain observed.
TomasDelSol: The fuel system was entirely replaced last year.

Need other suggestions

5

One area that gets overlooked on this kind of trouble is the alternator. Sometimes blocking diodes go bad inside it.

I assume you have a ammeter to check the current drain with. Here is a link to help you figure this out.

http://www.aa1car.com/library/battery_runs_down.htm

6

How old is this Camry?

Tester

7

Thanks for the help. The website you suggest provides a good comprehensive information of all the potential electrical causes that drains a battery, the problems that may arise by disconneticg the battery and what to do to fix the problem.
Yes I have an ammeter to do the tests. Thanks again.