Garmin HRT - no signal

Hey all !

Last few weeks I’ve not been able to use my garmin hrm with zwift - on pairing its continually coming up with ‘no signal’. I’m using zwift on a windows 10 laptop.

I’ve done a bit of research into this and seen there’s the possibility of the Bluetooth signal being stolen by other devices so I’ve already tried switching off garmin edge 520 / forerunner 935 / iPhone 6+ and still the issue persists.

Ive had one occasion amongst this where it paired when I opened my laptop and started the zwift app when not doing any cycling but every other time I get ‘no signal’

Can anyone suggest what is required to isolate the issue and resolve ?

Welcome Paul!

I already have 4 dead Garmin HRMs on my table… (which Garmin promptly sent a replacement for!)

If you don’t see it on your FR935, and have tried replacing the battery, then I would say get a replacement (actually, have one anyway, just in case.)

Another thing: washing the HRM strap overy once so often is recommended… give it a try - won’t hurt.

Hi there - thanks for responding.

The HRM works just fine on all other devices and is currently at 85% battery

It’s just zwift I can’t get it working on

hmm… I am a bit lost:

  • Is your HRM a Garmin HRM-Dual?
  • Are you connecting your HRM to Zwift using BT or ANT+?
  • Just to confirm: you are not using the Companion as BT bridge?
  • I understand you are able to get HRM reading on your FR935 (using ANT+). Is that so?

Can you try ANT+ connection on you PC?

I would also try shutting down all 2.4GHz sources, such as 2.4GHz WiFi, all BT devices, etc. (and connection your laptop directly to the router, not using WiFi…)

Thanks for this ! To answer your points:

  1. Yes I think it’s a Dual
  2. BT
  3. No direct to the laptop alongsite a set of P1 Powertap pedals
  4. Correct.

To try the ANT+ connection to PC I assume I’d need the USB dongle yes?

‘I would also try shutting down all 2.4GHz sources, such as 2.4GHz WiFi, all BT devices, etc. (and connection your laptop directly to the router, not using WiFi…)’

I have no idea what 2.4 GHz sources are. I’ve already tried shutting down everything I’ve ever paired the HRM with and it’s still an issue.

… based on your reply, I would “simply”:

  • Shut down all WiFi
  • Get a ANT+ dongle for my laptop

Kindly please update… good luck!

That doesn’t fix the issue though - I want it to work as it did for months and not just do a work around !

How would that work with my P1 pedals - so I’d end up with HRM connected via ANT and power pedals via bluetooth ?!


I was working toward the assumption your HRM BT is not working properly - only it’s ANT+ leg is. How about HRM reading using your mobile phone’s Garmin Connect?

And yes, you can mix BT and ANT+ in Zwift.

(btw, none of FR935/Edge 520 are BT…)

There a numerous posts about this bug affecting Garmin and ticker dual HR monitors.

From memory the only way anyone solved their problem was (they were using an iPad) was to do a factory reset of their iPad and load all apps back on. I believe this bug was introduced in the last update and is affecting a lot of people with dual HR trying to use Bluetooth (but maybe not all people).

Since you are on a pc the obvious thing to try would be uninstalling zwift. Ensuring that all folders and files for zwift are actually deleted. And then installing zwift again. The only data you’d lose is custom workouts and 30 day PRs (and if you really care about them there is a way you can back them up).

Ah thanks :slight_smile:

I think it’s working just fine - I can connect to my iphone via BT with the HRM no issues

Thanks - I’ll try that.

Assuming I just delete the app what else do you think I need to do to ensure all files are actually deleted?

All my data goes onto training peaks / strava hence not bothered in the slightest about local files

Use control panel to uninstall the program. Then go to documents and delete the zwift folder. Go to downloads and delete the zwift folder. Search your computer for zwift and have a look at those things.

Re-installed and it still has - no signal - !!

Zwift !!

I’d suggest you send a support ticket then to support and tell them everything. They are back logged so it will take more than a week (from other people’s experience). If you send additional requests/enquires your ticket gets automatically sent to the bottom of the pile.