What was found
AIRCRAFT RETURNED FLIGHT AS A CONSEQUENCE OF DURING CLIMB, AIR CONDITIONING SYSTEM WITHOUT FLOW AND ALTITUDE PRESSURE LIGHTS TURNED ON. DURING REVISION AIR CONDITIONING SYSTEM WAS FOUND TURNED ON WITHOUT PRESSURE AND FLOW, THE AUTOMATIC AIR CONDITIONING SHUTOFF BREAKER WAS TURNED TO OVERRIDE REESTABLISHING THE SYSTEM. AIRCRAFT WAS SENT TO THE HANGAR AND WIRING AND SECOND SEGMENT SWITCH WAS DETECTED GROUNDED. THE WIRING WAS REPAIRED AND AT PRESSURIZATION TEST WAS DETECTED SWITCH DAMAGED, THE SWITCH S1-296 WAS REPLACED IAW MM 21-31-09, TESTED CORRECT. TEST FLIGHT WAS PERFORMED AND AIR CONDITIONING SYSTEM OPERATED CORRECTLY.