August 21, 2014 - Have tried a battery change to no avail. Any other suggestions before I write it off and buy a new one? Also see How to get the Garmin heart rate monitor to work after a I bought a Garmin 735XT and the Garmin HRM Run chest transmitter about 6 months ago. I'm only getting about 30 hours use at the very most from the chest transmitter battery before having to replace it with a new one. Is this normal? I see that garmin states over 300 hours use from a new battery. I'm not getting a fraction of this for some reason. Was working fine until yesterday. Went from reporting 75% battery to 20% battery in a day and doesn't go to sleep properly. Only wear mine running, never swam or submerged it. Rinse the band every few runs and hang it to dry. Seems to be showing up in my Garmin connect app even the next day after it hanging still all night to dry. Observe the orientation of the front cover. The raised screw should fit in the matching raised screw hole on the front cover. NOTE: Do not overtighten. Replace the sleeve. After you replace the heart rate monitor battery, you may need to pair it with the device again. Troubleshooting. Then the battery on the Tri strap failed, was replaced, then failed again only a few days later. Got through about 6 batteries in one month before logging a fault with Garmin. Same problem with HRM Run or Tri, after 2-3 months of use with original battery ( short life time regarding 10-12 months annonced by garmin !) , the strap works 2 weeks HRM-Pro not record Running Dynamics. My watch is 945 (ver 5.50) and HRM-Pro (ver 7.10). The connection between my 945 and HRM-Pro is ok and the connection between GCM with both my 945 and HRM is ok too. But I do a run activity on my watch, it notice that the connection between my watch and HRM-Pro status is Connected, after I finished activity – Garmin HRM-PRO (original) – Garmin Elevate V4 Optical HR Wrist Sensor (in a Garmin Forerunner 255 watch) – Oura Ring V3 optical HR sensor in workout mode – Polar H10 chest strap – Polar Verity Sense Optical HR Sensor – Whoop 4.0 Band. But, here’s the simple and boring truth: The data was boringly perfect. Last month or so HRM Pro data is totally ubreliable. Sometimes it doesn't measure running dynamics data or does it half of the run leaving some empty areas in the graphs. Sometimes it shows wrong HR. For example durning the interval runs or threshold runs it shows my HR -20bpm or even -30bpm compared to real HR. Rpzk.

garmin hrm pro not working after battery change