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Q: the battery won't stay charged.

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my battery keeps going down, and won't stay charged more than a week. the local auto shop and Ford just want to sell me batteries. (4 already) there is a parasitic draw somewhere but I can't find it what is the best approach to locate this problem? The alternator was replaced but battery still went down Thx a mil
My car has an automatic transmission.

A: I would first verify that the vehicle has a...

I would first verify that the vehicle has a drain above 200 milliamps by disconnecting the battery's negative cable and putting an amp tester between the post and clamp.

The test should be done correctly by having the tester attached and touching the clamp to the post and when removing and getting the amp reading. If the test is done properly and everything is off, then there should not be more than the 200 milliamp draw.

If it is more than that, then I would start removing one fuse at a time in the engine fuse box until I isolate the draw to a certain circuit. Then I would trace the circuit to see what is drawing the battery. For example, you can try opening your trunk an checking the trunk light to see if it is hot as soon as you open the trunk. This indicates it was on when the trunk was closed.

If you would like help finding the parasitic draw, a certified technician from YourMechanic can come to your home or office to diagnose your car's battery issue and make any needed repairs.

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