Puzzling battery drain
 

I have a 2013 Mazda3 Hatchback with 70k miles. I just replaced the battery. If it’s not run for four days it won’t start.

I disconnected the negative battery terminal and put a current meter between the battery and the lead and am measuring a 1.5A current with the car off.

I pulled every fuse, one at a time and measured current as above. Removing the #46 fuse dropped the leakage current to 1.2A. Removing any other fuse did nothing (still had 1.5A leakage).

I’m presuming the .3A on the #46 fuse is normal and that I have a 1.2A unfused (at least in the fuse box) leakage. I noticed there appears to be a fuse on the positive battery terminal.

Anybody know what loads are infused in the fuse box (or have a manual with a complete wiring diagram)? Perhaps the starter? Alternator?

Other ideas of what might be going on?

Other information, possibly unrelated: we recently had the water pump replaced. After that work the Bluetooth functionality no longer works and I can’t get it into the Bluetooth setup routine.

I had a similar problem on my 2010 Mazda 3. Ended up replacing the Bluetooth Module which I purchased on ebay and the battery drain problem went away.

@ronb amazing thanks for the info. I guess I’ll go ahead and replace the Bluetooth module.

Out of curiosity, did you also check leakage current while pulling fuses and find no fuse that eliminated the leakage current?

I did detect current drain. I don't remember if I found a particular fuse that stopped it because I ended up replacing the Bluetooth module while I was troubleshooting it and it was almost two years ago.