PSA: Look at the heart rate sensor of your fenix 5. Has it cracks like mine? If yes, it's a common problem. Send it to Garmin and get a free replacement. Do
Heart rate is still working but I noticed the sensors glass covering seems cracked/smashed… should I replace the watch? - fēnix 5 series - Wearables - Garmin Forums
F5x Cracks on HR sensor resin due to curing fault - fēnix 5 series - Wearables - Garmin Forums
Garmin Venu review: Garmin's first OLED smartwatch
The HR sensor glass of my FR645 is cracked and I don't understand why. I literally only take off the watch to charge it... Did this happen to anyone else? : r/Garmin
Preventive maintenance for heart rate sensor cover - Fitbit Community
My heart rate sensor is cracked - vivosport - Health & Wellness - Garmin Forums