Garmin Cadence sensor V1 problems

Hi, I just started with Zwift a few days ago, and have the following setup:

Samsung Galaxy Tab S4
OnePlus 7T pro
Elite Suito trainer
Garmin v1 Cadence sensor with new battery
Garmin Fenix 6 Pro

I paired all devices via ANT+, including the cadence sensor, and my Fenix 6 is sending my heart rate via ANT+, into the Zwift app.

The cadence sensor is both paired with my Fenix 6 and Zwift Android app, and I see my cadence value 100% stable all the time, on the Fenix 6.

The trainer and heart rate works fine, but into my first ramp test workout, the cadence function stopped working, and I have not been able to make it work afterwards. I then installed Zwift on my Oneplus phone.

I am able to pair all sensors, including cadence sensor, but the cadence sensor seems unstable in the pairing screen, “no signal”, typically, and the cadence value seems to be stuck at 56 quite often. When entering the ride screen, no cadence values are visible.

During the ride, a have tried to enter the pairing menu, and repeat pairing of the cadence sensor, but normally the Zwift app crashes, (Zwift quits, abruptly) when doing that. I have checked my Fenix, and the cadence value is updating continuously, no problems at all.

I paired the cadence sensor to my Fenix after I encountered problems with it in Zwift, so I am somewhat worried that it might disturb Zwift in some way. I will try to shut down my Fenix later today, and see if it makes any difference,

On my Oneplus phone, I experience the same problems as on the Samsung Tab S4, everything works fine, except for the cadence sensor. I am only using ANT+, no bluetooth.

Hope we could find out, what’s going on.

An update/solution:
I set up a debug session; “adb logcat”, and when holding the cadence sensor in my hand, I was not able to make it fail.

I then attached the cadence sensor to the crank arms, and it fails immediately. So the cause is most probably related to the RF signal strength.

I placed a 2x4 lego brick between the crank arm and the sensor, and it seems to work better now.

The problem is probably solved,


It seem like the problem is not necessarily related to RF level. I was not able to complete a ride this evening with a funtional cadence sensor.

I connected my android tablet to my computer and started “adb logcat” while keeping the cadence sensor close to the android device, while rotating it.

I am able to pair the device: 58879, but it seems that some errors occur after pairing.

I can provide the android log file if I find a way to attach a link.

After pairing it ends typically with this type of log message:
11-23 22:17:21.307 18045 18045 I BikeCadence: Device: 58879 : DEAD

My Fenix 6, reads the cadence sensor withount any issue, during my workouts.

I hope a developer can take look and see if if can be fixed.