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Mazda 3 Battery Drain

Hello - hope everyone is staying safe in this unprecedented time....

I purchased a new Mazda 3 GT in 2016. During the second Canadian winter, if I left my car parked for more than about a week it would be difficult for the engine to start. The battery seemed dead. Jumping it solved the issue, so I passed it off as a temperature thing. This persisted every winter since. I am on my third Costco battery.

Now it is Spring 2020 and my batter drains itself after sitting in the garage for a few days. A multimeter confirmed that the battery was ~7 V, hence the car would not start properly. When I jumped the car, it runs and can charge back up to 12V fine. When running the voltage is ~14V so the alternator seems to be okay. If I unplug the negative terminal on my car while it is parked, the battery stays charged. Hence, I figured it was a battery drain problem.

I checked the current on the battery and it pulls ~1.6 A when off, which seems high. My wife's KIA is at 0.7 A when parked, so I knew something must be up.

When I pull FUSE 5 DOOR, the most significant drop (0.8A) occurs. The battery is then sitting at a 0.8 A current. The manual says this is for the overhead dome light, but how does a single light pull 0.8A when off? I learned this was also for the door mechanism, because the FOB doesn't work when that fuse is pulled, only manual entry with the key.

My door locks make a weird rubbing/squeaking sound when unlocked/lock. That has been my normal for ~2 years. Last time I had the vehicle serviced they said they couldn't "reproduce it".

TL;DR - Does anyone know if a 0.8 A draw for FUSE 5 DOOR on a 2016 Mazda 3 GT (when off) is normal?
 
Have you measured the current across the fuse but without the dome light in place? I would try this with and without the door opened. Also, try it with and without the fob close by (wait 5 to 10 mins after removing the fob from the vehicle before testing)

Some good info
 
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