What was found
AIRCRAFT DID NOT PRESSURIZE DURING FLIGHT TO PHOENIX FROM PARKER, AZ. CHECKED GEAR SQUAT SWITCHES AND WIRING. PERFORMED GROUND PRESSURIZATION OF AIRCRAFT WITH APU. APPROVED AIRCRAFT FOR RETURN TO SERVICE. MAINTENANCE CHECK FLIGHT PERFORMED. AIRCRAFT FUNCTION NORMAL PRESSURIZATION IN BOTH MODES OF OPERATION, MANUAL, AND AUTOMATIC. LANDINGS, 4,877.