As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) THE STUDENT PILOT WAS DOING AN ENGINE RUN PRIOR TO FLIGHT. WAS UNABLE ON THE FIRST TRY TO COMPLETE THE MAGNETO CHECK AS THE KEY WOULD NOT TURN FROM THE BOTH POSITION TO THE LT RT OFF POSITION. AFTER SHUTDOWN, THE STUDENT WAS ABLE TO SELECT OFF ON THE SWITCH. THE SWITCH THAT WAS INSTALLED WAS A SWITCH WITH A PUSH TO START FUNCTION. FOUND THE SWITCH STICKING INTERNALLY & REPLACED IT WITH A NEW PUSH TO START SWITCH.