My 520 can't remember my Cadence sensor from one ride to the next. When I turn it on and start my ride, other sensors are detected but to get Cadence, I have to fiddle with it - navigate to the Sensors menu, find the Cadence sensor and add it. I have tried spinning the crank immediately, thinking there was some sort of timeout, but no change in behavior. Once added, it works fine ... until the next ride. The cadence sensor had no problems until recently. What would cause this flakey behavior?
I'n not sure why this is happening, but if I had this issue I would just try some general trouble shooting steps. First I would delete the sensor from my 520, I would then re add it and give it a different name. I would also try changing the battery in the cadence sensor. If the problem persisted, I would do a hard reset of the 520. After exhausting those possibilities I'd call Garmin support, it could be the sensor is defective.
