General Troubleshooting Guide for MobiFlight and MSFS2020

When something does not work

When things do not work, it is good to take a practical approach to debugging, checking one thing at a time.

There are three main areas in MobiFlight that need to be set correctly in order to everything to work:

1. Check that your arduino is recognized.

This is indicated by a green checkmark on the MobiFlight Connector window statusbar, and it will be listed in the small dropdown menu that opens from the arrow.

If you do not see this, your Arduino is not recognized. See Arduino modules documentation - many of the Chinese clones require that you install the CH340 serial port driver. This is also covered in the above.

2. Check that your button / encoder is wired and configured correctly and works.

This is done by enabling the log in MobiFlight Connector. (Extras -> Settings - select logging with the default log level of "Info" is enough) This will show all button presses and releases and other arduino pin events on the log area of the Mobiflight window.

If your button or encoder shows nothing in the log, nothing will be sent to the simulator, because MobiFlight does not see your switch or button being pressed. Make sure you connect things properly and that the wire connections that are secure, and that you have selected the correct arduino pins. Also make sure you "upload configuration" with the toolbar button after you make changes, so that the pin config is stored also on the arduino. If you forget this, Mobiflight will warn you about unsaved changes though.

3. Check that your sim connection works.

You should also have a green checkmark for Simconnect when simulator is running. IF you use MSFS2020, you do not need anything else as MobiFlight uses the built in Simconnect interface on MSFS2020, and the provided MobiFlight WASM module that you should also install. If you use FSX or Prepar3D, you do need FSUIPC for the connection, respectively. For X-plane you can use the provided dataref/command interface and presets. For X-Plane, the XPUIPC interface naturally also works, but the direct dataref/command interface should be a lot easier to set up.

Note that you need to restart MSFS2020 after you have installed the WASM module, you need to restart MSFS2020 once to make it see the newly installed moduile. This will also be indicated with a green checkmark next to the "WASM Module" in the Simulator dropdown.

Try with a simple config item like parking brake first.

4. Many add-on aircraft, especially the popular FBW A320 add-on change frequently

..and many of the events unfortunately also change over time, so when you get started with MobiFlight, start with something simple first so you know that one works first.