Author Topic: Garmin 800 not showing distances.  (Read 1871 times)

Garmin 800 not showing distances.
« on: 10 June, 2020, 08:39:42 am »
I've got a Garmin 800 which, since it's an 800, is relatively old.
The past few days I've been using it on a commute to and from work.
Before I set off, I give it time to find the satellites and all is good until I've gone 300m-2km and then the speed display drops to zero and it doesn't record distance.
Switching it off/on again starts it normally for another few hundred metres and then it stops displaying speed and distance again.
When I upload to Strava I can see the whole of the route that I've done but the recorded distance is only a few hundred metres.

Any ideas ?


  • It's mostly downhill from here.
Re: Garmin 800 not showing distances.
« Reply #1 on: 10 June, 2020, 09:33:57 am »
Sounds like it's got it's branez scrambled a bit.
One of my 800s lost its branez in a slightly different way a while back.

The tracklog and summary data are separate things in the FIT file, which may explain what you see on Strava.

In the first instance, I'd do a Master Reset:

Failing that, I had to re-flash the firmware.
Note that it won't re-flash the current version of firmware which it has.
If it sees a gupdate.gcd file with the same version as it currently has, it just silently deletes it.
So I had to install an older version first (it's fine with that), then re-install the current version.

I used the library of firmware here:


  • rothair gasta
Re: Garmin 800 not showing distances.
« Reply #2 on: 10 June, 2020, 02:58:14 pm »
Are you using a speed sensor on the wheel?
If that isn't working, it may not record any distance. Check the magnet is lined up, or change the battery in the sensor.

Re: Garmin 800 not showing distances.
« Reply #3 on: 15 June, 2020, 12:08:57 pm »
Thanks for the tips.
I did the Master Reset and, on the 2nd attempt, it appears to be working normally again.
I'm using the Strava app on my 'phone as well, just in case.
The speed and cadence sensor is working fine; the Garmin was recording cadence but not speed. The magnet is lined up.