Pre-Arm Safety Check fail after flash APMrover2 -> Pixhawk


When I flash APMrover2 code to my Pixhawk, the Pixhawk blinks a yellow light twice repeatedly. I’ve figured out that this means it is failing a prearm safety check.

I have not changed the code at all. I just cloned the diydrones/ardupilot code and followed instructions on this page.

I can use APMPlanner2 to load the Rover 2.5 code and that code works perfectly. Does anyone know what could be wrong?