Protective cover over heart rate sensor is punctured.
1 of the 3 windows of the protective cover of the heart rate sensor underneath the watch is punctured. There is some condensation in there and battery drains from 100% to 0% in less than 12 hours.
Im thinking the puncture (and possibly condensation) messes with the sensor thus draining the battery.
Seems easy to just peel the cover back and replace it, but i havent found a part or anybody that has replaced it before. I dont want to just put clear 3M tape over it like one guy did.