This discussion has been locked.

You can no longer post new replies to this discussion. If you have a question you can start a new discussion

New cadence sensor -> very erratic display

Hello dear list members,

I could use some help about my new cadence sensor.

I had to replace the previous one, as my old bike disappeared in a robbery.

I still have the Edge 520+, but I had to purchase a new set of sensors.

I noticed that these new ones are different (slightly more compact).

The pairing went fine for both sensors (so I trust that both are compatible with the Edge 520+).

But the cadence display varies much too quickly, typically 90 -> 80 -> 85 and so on, in a matter of seconds. That is, without shifting, and at a constant speed, so the cadence should be pretty constant. It even displayed 9 rpm while I was coasting... However, at times, the display becomes more steady.

For what it matters, I also noticed that the battery level is not displayed on the Garmin Connect website (whereas I can see the level for the speed sensor, which works flawlessly).

What do you think I should try? Do the pairing again, or perhaps a new battery? Position on the crank arm (it's in the same place as its predecessor)? Or is it maybe a faulty cadence sensor, which I should return?

Thanks in advance for your advice. Happy 2022, Daniel (France)

0 aweatherall over 2 years ago

Did you by chance pair to over BLE and not ANT. If you look at the sensor details for the cadence sensor it should show what protocol you paired over.

0 dclement8 over 2 years ago in reply to aweatherall

Thanks for your answer! However, the only thing I can see under the sensor details is the sensor Id (a 6-digit number). Maybe the protocol was chosen at pairing time? I can't remember that. In this case, maybe I should repeat the pairing process?

0 Scillonian over 2 years ago in reply to dclement8

The sensor need to be active for the full details to be shown. When the sensor is sleeping only the ID will be shown.

Turning the cranks a few times should activate the sensor. The LED on the sensor will flash for a few seconds when the sensor becomes active..

0 dclement8 over 2 years ago in reply to Scillonian

Hmm... After activating the sensor, besides the ID, I can see the following details under "product info": battery condition (average)/software version/manufacturer/product number/serial number.

Nothing about the pairing mode. Is there something wrong here?

0 Scillonian over 2 years ago in reply to dclement8

As far as I can tell the Edge 820+ only supports ANT+ sensors so there will be no entry for the connection protocol. (Only the more recent x30 family of Edge support Bluetooth sensors.)

You could try different mounting positions, event try the drive side. Attaching the sensor to the chain ring spider worked for me to (mostly) cure cadence spikes I was getting.

Next time I go for a ride I will monitor my cadence sensor and see how it behaves.

0 dclement8 over 2 years ago in reply to Scillonian

Well, during my last rides, I could get some improvement by installing a fresh battery and moving the sensor closer to the bottom bracket. There are still some glitches in the readout, but perhaps less than before.

I guess it's the best I'll ever get with _this_ sensor. Maybe I'll try and find the older model (same as delivered with the Edge 520+), perhaps it's "more" compatible...