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It takes 1-2 days for the battery to drain completely on my 2006 Mazda 3i sedan.
The mechanic says that the battery, alternator and starter are OK and that I have some electrical problem around the drivers door.

Earlier this year I changed the window regulator because the window wasn't fully closing but this did not fix it. At the time I noticed that the window motor gets quite warm. In addition, the drivers window does not go up most of the time. I have disconnected the power on the window motor and the window master switch to test if this may be causing the battery drain but it was still drained.

Also - my "door ajar" dashboard light is ON all the time even tough all doors are well closed.

Earlier this year I was replacing the cabin filter and I am not sure if anything that may be related got screwed up.

I don't see any other lights that stay on when the car is off.


Can this dashboard light be draining the battery?
Would you replace the entire door lock to fix this light?
What other steps can I try to find the battery drain source?

Thanks!
 

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Demon Spawn
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it sounds like an issue with the wiring running to a door somewhere (mechanic if you trust him says driver front so start there) check the molex where the wires pass through the door hinge for cracks and pinched wires or missing shielding on wires. what you can also do, it is tedious but will let you know for sure which circuit the issue is in, you can get a voltmeter and set it to amps hook it to the battery car off and look at the read out it should be no more than about 1 amp with everything off doors shut and keys out of the ignition. if you get a higher readout you have parasitic drain, which you have already discovered. the next step in this would be to have someone, if you can get someone to help, pull 1 fuse at a time and you watch the amp read out, if it drops when they pull a certain fuse make sure they note which one it is labeled(or if alone same thing just note which fuse you have pulled). then you would need the wiring diagram for that circuit which most dealers will provide you free of charge and the Haynes manuals have some basic ones. and simply follow it from the fuse box out until you find your problem. electrical demons like this are a nightmare even for a highly skilled mechanic and you may not have any luck finding the source, but paying for a fix will most likely cost a small fortune so try to find which circuit it is in at minimum first before you seek professional help. That way you can tell them I have something wrong in lets say window motor fuses circuit can you check this circuit as it seems to be the one causing my parasitic drain issue.
 

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I had this happen to my 2006 a few weeks back. It all started with my factory alarm triggering randomly. My battery was old, and due for replacement, so I started there. Alarm would still go off randomly. Security light was also flashing oddly.

Turns out, the mini-position switch in the hood latch was intermittent, making the car trip the alarm.

It was cold and I didn't feel like working on the switch, so I unplugged it, just behind the radiator core support. That stopped the random alarm triggers.
As I later found out in a dark corner of the internet, when one of these position switches is in the "open" state, the ECU thinks the car is being serviced, so it does not go into sleep mode. The ECU being "on" drained my battery in a day.
My solution was to solder the 2 wires together, so the car thinks the hood is closed.

If your problem isn't the hood switch, could it be a sensor/switch that thinks a door is open? Not sure where those are located.
Hope this helps, if you find a fix, post about it. I had a really hard time finding my solution...I should write it up with pics, for the next guy that runs into an issue.
 
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