Saturday, 17 March 2012

How To: Reset a Garmin heart rate monitor

I was starting to panic, as I am running the Liverpool half-marathon tomorrow and the chest strap monitor that came with my Garmin Forerunner 305 suddenly stopped working yesterday.  Previously there had never been any problem with the Ant+ device - the HRM1G - so I was a bit concerned.

After replacing the battery twice, I was no further forward.  I even tried resetting the Forerunner unit itself.

A couple of Google searches later I came across this thread suggesting reversing the battery.  I tried it, and the HRM1G registered straight away with my Forerunner unit.  How very relieved I am.

Although the Garmin forum thread suggests that the polarity has been reversed, in effect the upturned battery is just short circuiting the two contacts due to the shape of the battery.

A useful hint to know.


  1. took this advice and can't recommend it. Almost impossible to get the upside down battery out, something I had to do straight away as it made no difference to my HRM1G.

    1. You are right, a paperclip is a better solution for the hard straps. On soft strap monitors, just remove the orange rubber ring encircling the battery, before you insert the battery in reverse.

  2. Oh dear, I'm sorry to hear this did not work for you. Maybe I just got lucky, but it worked first time for me.

    After your experience with a stuck battery, better advice for others would simply be to short the two contacts with a coin, screwdriver, it piece of wire. Thanks for your feedback.

  3. You're a legend!! Worked great for me

  4. Same issue, same batteries changed and same panic one week before a race !!
    It worked for me too ! Thanks a lot !

  5. Work for me as well! You don't have to insert the battery all the way, you just need to lay it down to angle so that the positive terminal surface touches both of the contacts.


  6. This solution is soooo awesome. I almost gave up on both of my soft straps, until I found your post. I worked on both non-functioning straps. Thanks a lot.

  7. Perfect, work for me.


  8. Perfect, worked for me. was ready to buy a new one