Related

Forerunner 955 Solar – WHR firmware shows 0.00.00 after update to 27.09 (update keeps reinstalling)

3778585

Hi everyone,

After updating my Forerunner 955 Solar to software version 27.09, I’m seeing what looks like a firmware issue with the wrist heart rate sensor (WHR).

In About → Software Versions, WHR now shows:

WHR: 0.00.00

Before the update, this value was not zero. Since updating:

  • Wrist heart rate does not work

  • No HR data is recorded during activities

  • Rebooting the watch did not fix the issue

Additionally, every time I put the watch on the charger, it starts “installing an update” again, but it is always the same version (27.09).
The update process completes, but the problem remains and WHR stays at 0.00.00.

Other firmware components (GPS, BLE, CIQ, etc.) show normal version numbers.

I’ve attached a screenshot from Garmin Connect → Device → About showing the issue.

I also found that other users reported the same problem after updating FR955, including this Reddit thread:
https://www.reddit.com/r/GarminWatches/comments/1kq7v0t/garmin_fr955_nearly_ruined_heres_how_i_saved_it/

This looks like the WHR firmware may not have been flashed correctly during the 27.09 update, and the device may be repeatedly trying (and failing) to apply the same update while charging.

Questions:

  • Is Garmin aware of WHR showing 0.00.00 after the 27.09 update?

  • Why does the watch reinstall the same update every time it’s charged?

  • Is there an official recovery procedure (forced sensor firmware reload, downgrade, etc.)?

  • Should affected users contact support for replacement, or is this software-fixable?

Thanks in advance for any guidance. Happy to provide logs or additional details if needed.

  • 0

    One way to force an update is to go into the hidden menu (System → About → press LIGHT button eight times) and select Reinstall Software. That might work.

    Some people have found that cooling the watch (eg. an hour in the fridge) before applying any updates helps. (This points towards FLASH memory problems.) I wouldn't recommend putting it in the freezer as the screen probably won't be happy to be taken down to -18°C.

  • 0 in reply to nowster

    I tried it, it didn't help, thank you!

    I hope Garmin team can do something with it and next update fix the issue. It happens with my device because of the update. I can't believe if it's hardware related issue, because I even didn't have any sport activities during weeks bedore the update. What happens with Garmin's QA, I use garmin devices since 2017, many updates of my watches before everything were okay, I couldn't think I should disable auto updates.

  • 0 in reply to nowster

    I tried reinstallaction again, and noticed that it says Update failed. 

    That says it's definitely firmware update issue, support is ignoring me, it's sad.