When you start up you Turnigy 9X transmitter, it might beep and say “switch error”. The users manual doesn’t mention this for some reason and it can take a while to figure out how to solve it.
What you need to do is to set the switch in a specific position. The switches on the front must be set towards the top and the switches on the top must be set towards the back.
I hope this could solve your problem with the switch error.