My Garmin has failed to read my heart rate for a few weeks now (probably longer as I actually rarely look at the trace once downloaded). Rather than replace the battery again, I thought I’d use the spare strap that Garmin sent me last time they replaced my watch. Although I knew the transmission between strap and watch was coded, what I hadn’t realised was that the pairing was a one off process and the watch thereafter remembered which strap it should be talking to. Fortunately it’s a simple matter (once you’ve consulted the manual) to select Settings > General > Accessories from the main menu and then, for the heart monitor, select Restart Scan. And voila, I once again have a heart beat. I’ve even added the heart rate back on to the main display of my watch so maybe I’ll actually start looking at it!