Before the problem
Yesterday I configured a APM2.6 to plane. Everything was fine, gyro works, 6 flight modes were programmed in Tx and work, GPS also works, among other things.
Second day into bench testing, when toggling the flight mode switch in transmitter, flight modes with PWM values did change in “Flight mode” page of Mission Planner, but the flight mode in HUD did not change. All the servos did not work.
I bypass the APM2.6 to test the servos, they do work, meaning there is no problem with the receiver.
Has this something to do with the 3.3V regulator, or some part of the circuit has burnt ? Any help is appreciated.