What's draining my battery after a deer ran into the driver side door?

2011 Mazda CX7, 115k. About two weeks, my daughter was driving her car and a deer ran right into her driver side door. She was okay and the deer stumbled off.

We put in an insurance claim, b/c there’s a big dent in the driver side door (nowhere else as far as I can tell), the door opens and closes but you have to finesse it a little, and the driver side window isn’t working. All the other windows work fine.

Yesterday, the battery was dead. I have it charged and drive the car for 40 minutes on the interstate. This morning, it started but still hesitated.

Does anybody have an idea what might be draining the battery, and what I can do about it? There’s no dome light on all the time, no tone, no Open Door warning light, etc. There’s no auto lights, you have to flip the switch to turn the headlights on/off. I tried pulling the fuse marked Horn and PWindow but still had the hesitation this morning. BTW, all the windows work fine still, even from the back, so I’m not sure what the PWindow fuse powers. Yes, I put all the fuses back in after it hesitated at start up this morning.

Lemme put on my wizard hat and grab my crystal ball… Nope, can’t tell you what is causing it. My wild guess is the door switch is staying open so the car won’t go to sleep.

If you really want to know what is keeping the car awake, your shop needs to run a parasitic draw test as well as plugging a scanner into the car to read which signals might be triggering the draw. Both of these tests require tools. The draw test, a good multimeter. The scan, a pro level OBD2 scanner.


There’s a lot wires in the door for the power window, door lock, etc…

The impact may caused the door skin to dent in and pinch a wire causing a short to ground.


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OK , add that problem to your insurance claim .


There is a good chance this battery drain is all coincidental and has nothing to do with the deer strike. Two weeks went by between the deer strike and the existing problem so maybe testing the battery and cleaning the battery cable ends might be in order.

A quality body shop should be able to locate the problem while repairing the door-skin.

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A deer ran into my sons’ driver’s door about 6 months ago while he was driving home on a dark wooded road at night. dented his door and he could not open it and the window would not go down. it took off his side mirror and even his headlight would only work intermittently, even though the deer did not hit anywhere near it. the P window fuse should just be for the power windows. the only thing I can think of is maybe something electrical is now hitting the inside of the door skin causing the drain. but that’s just a guess.

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