Hello,
I know there are threads regarding this issue, but they are all locked. So I cannot add to them. (Also found some on the Edge 840 forums eg https://forums.garmin.com/sports-fitness/cycling/f/edge-840-series/356573/all-sensors-disconnect-shortly-after-activity-start and https://forums.garmin.com/sports-fitness/cycling/f/edge-840-series/340641/840-drops-all-sensors-when-starting-an-activity#pifragment-1290=2)
New Edge 1040 User here. Went on 3 rides so far. First ride no issues. Second ride the issues started and were exactly the same on the third ride.
ISSSUE DESCRIPTION: When I wake the Edge 1040 all sensors connect, then when starting the ride right away the Garmin Dual HRM, Garmin Varia RTL 515 and the 4iiii Power Meter will drop. I need to power down the device and restart, then they will reconnect. Obviously I have to stop before I can do that. Not really ideal when you just took off (it is downhill from my home right away).
The only change I made between ride 1 and ride 2 was that I installed the ConnectIQ store and added 2 data fields: WindField and hGradeMax. I am on the latest firmware 21.18.
From what I've read, other users have had the same issue in relation to ConnectIQ. Over a year ago... This should really be fixed by now, because this literally breaks the core functionality of the device... I tested uninstalling the datafields also removed ConnectIQ from the device as I have read on those linked posts, that this may be a solution. IT DID SOLVE THE ISSUE.
However this is not a satisfactory solution. The sensors should work, even with ConnectIQ. I really like the WindField data field.