Garmin HRM Swim casing cracked after battery replacement
I'd like to start by saying that I did not overtighten the screws... I'm posting this video. Hoping to help someone out there in case their Garmin Heart rate monitor stops working, in my experience this HRM stopped working twice and I was able to replace the battery each time. And spray electrical contact cleaner inside of the casing, wait for it to dry then It came back to life.
If your HRM stops working and you're looking at video, I'd recommend inspecting the oring and the casing for any cracks, if cracked, spray electrical contact cleaner inside the casing and wait for it to dry (preferably in front of a fan) then apply sealant to the cracked areas and replace the oring... do not wait for the sealant to dry, close the casing with the new battery while the sealant is still somewhat wet so that it can take the shape of the battery cover and provide a good seal.