I don't know anything about the Garmin, but low batteries will do this on my Polar, either in the main unit or, the one people forget, the sensor.
I also had a case recently where the heart rate monitor kept insisting I was dead ... and the speed sensor seemed to agree. I set a pretty good pace for a corpse but did wonder if one was interfering with the other thanks to a low battery somewhere in the mix.
I wonder what it would do it for disabled the speed/ cadence sensors and just went with the GPS. That would narrow down the problem perhaps.
In the words of the IT crowd "Have you tried switching it off and on agin?"
Seriously, I've had a few problems with mine, but they've all been solved by switching it off, putting it somewhere where it can get a fairly good reading on satelites, switching it on and leaving it for a while. CLP originally suggested it to me, not sure why it works (he's the tech geek out of the two of us, not me) but it's solved a few problems for me. Worth a try, and as long as you don't put it somewhere it can be stolen, nothing to loose by trying :)
Possibly also check if the magnet on the back wheel is close enough to trigger the sensor? I've bumped mine a few times and had odd distance readings from it because of it. Check that the cadence displayed in the head unit makes sense for the cadence you are riding.
Hope this helps.
make sure that you have the latest firmware installed. Just from memory, there's were issues with auto pausing on one of the garmins, but i can't recall whether it was the G800 or G500.
is it actually picking up the speed sensor? ie when you are travelling at decent speed is it displaying that speed correctly? waht about cadence? if so, that might exclude a flat battery in the sensor.
It was the 500. Ive disallowed autopause on my unit and it's solved the problem..just have to remember to manually stop the timer if I get off the bike for a coffee.
Did you stop the lap clock at anytime?
I would try changing the battery in the cadence sensor, and then re-inialising it. Sounds like the sensor is dropping in and out.
Agree with others
2. go into setting & ensure cadance sensor is connected
3. if so, check whether you have you have accidently nominated a km/h value to activate "auto pause"
4. check updated firmware
5. there is a re-set feature, by pressing two buttons at once
With the Edge 500, that two button combination is the Power/Light (upper-lefthand corner) and the diagonally across and down Lap/Reset button.
check whether you have you have accidently nominated a km/h value to activate "auto pause"
Cripes, who'd want that. As far as I'm concerned, if I can get the thing moving it can record the effort, especially if it's up a steep hill.
I think it's usually used to auto-pause at traffic lights.. so the default value is zero. however if you were relying on the gps for speed readings then you might get small fluctuations in speed even while stopped, so you can set a threshold.. say 1 or 2 km/h to make this setting more useful
P.S. if you use the reset feature you will be required to reset all your display screens, bike details and personal details
this is a last resort. if you go to garmin forum site there is some useful information
i have contacted Garmin Australia previously and found them to be fairly useful, it just may take 3-4 days for a response