I'm connected to a training app but Fliiiight doesn't change resistance. – 4iiii Help Center

Start by Troubleshooting Connectivity if the trainer applies consistent resistance, and is reporting power, either consistently or intermittently.

Start by Troubleshooting Fliiiight if the trainer is connected but reporting no power, and/or there is no resistance.

Troubleshoot Connectivity

Some apps have the option to connect with the trainer as a powermeter or source of power only. Make sure that you are connected as a smart trainer. Apps may also use the terms “controllable” “FTMS" or "ANT+ FE-C trainer" instead of smart trainer.
Some apps are capable of receiving power data, but not of sending smart trainer commands. Apps created for or partnered with a specific trainer brand may not control other trainer brands, control only a limited number of trainer models, or send commands to other trainers over ANT+ but not over Bluetooth. Check with your app's support resources. Compatible apps must send commands over one of two standard smart trainer protocols:
- ANT+: FE-C
- Bluetooth Smart (BLE): FTMS

Troubleshoot Bluetooth and ANT+ interference in the environment if Fliiiight stops responding to new commands partway through your ride, or if it stops and starts responding.
Make sure the trainer is not receiving commands from another app:
- Check the status light to see if it is paired with more than one app or device over Bluetooth. (Note that if only one Bluetooth channel is connected, the trainer can still be connected to another over app or device ANT+).
- Close all other training apps.
- Put other devices you have previously connected with into airplane mode briefly to force them to disconnect.
If you've recently updated the trainer firmware, reboot the phone or device running your training app. Occasionally, devices will cache information from previous firmware version, that interferes with their communication with the new firmware version.

Note: As of 2019, Zwift on Android does not currently support Fliiiight's connection protocol. Zwift is compatible with Fliiiight on Windows, Mac, iOS, and Apple TV.

Troubleshoot Fliiiight

If Fliiiight does its initial start up sequence, but then does not provide any resistance, and connects to the app but does not send power, it is having difficulty detecting the wheel. See troubleshooting for Fliiiight is having difficulty detecting the wheel.
Your trainer may have shut down because it's low on batteries. Charge the trainer.
Check if the magnet arrays are able to respond to manual commands.
Check that the magnets are level with the wheel rim. If they sit above or below the rim, they won't create enough resistance. Align the unit with your wheel.
Contact support. Let them know what troubleshooting steps you've tried so far.