As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, THE LANDING GEAR FAILED TO RETRACT. PILOT RETURNED TO DEPARTURE. FOUND LT MAIN GEAR SQUAT SWITCH FROZEN AND THE INTERNAL MICRO SWITCHES REMAINED IN THE GROUND MODE. REPLACED SQUAT SWITCH WITH NEW SQUAT SWITCH. ALL WORK PERFORMED IAW SRM. (K)