I bought a 2015 mazda6 grand touring with technology package and with i-eloop last Saturday. Parked it in garage, and on Tuesday morning it had dead battery. After a battery jump by Mazda roadside service, drove it to dealer. They think the fob was left too close to car. Fob was about 20 feet away behind a close door. No lights were left on. Service department had to put battery in some water to cool it off, plus had to reset many components of the car. Car did start today, and I did move the fob 10 more feet away and in a breadbox. Anyone know possible cause for the dead battery?

 

Did you lock it?

 

Car was unlocked

 

It is possible that ECU was not completely shut down.
I hope Grim Reaper responds as he is the mazda mechanic expert in this field. I was hoping you would have responded last night as Grim Reaper is in Australia and usually responds early in morning.

 

Yep,

If you don't lock the car when not in use the modules can stay in standby mode waiting for your next command. This can flatten the battery over a few days, depending on what the battery condition is to start with. Also any extra electrical accessories can accelerate the drainage.

No, its not stupid, no its not dumb. Common sense is to secure your car, ie lock it, when your away from your car. ( not to mention insurance complications)

In Australia, If you park your car in public, leave it unlocked and walk more than 5 meters away from it your are committing a traffic offence & can be fined by the police.

That is way more than my usual 2 cents worth

 

Its 10pm here in Queensland, so its somewhere between 4am & 7am Friday Canadian time. Right?

 

According to my time zone your post was done @ 7:10 am.
Clocks go ahead 1 hour this weekend, then it will be 8:10 am.