What was found
AFTER TAKEOFF THE AIRCRAFT WOULD NOT PRESSURIZE. WE USED QRH (CABIN ALT) FOR GUIDANCE, AND TRIED MANUAL MODE AND THE AIRCRAFT STILL WOULD NOT PRESSURIZE. REPLACED DEFECTIVE CABIN PRESSURE CONTROLLER IAW AMM 21-31-13-400-801, NO DEFECTS NOTED. REPLACED DEFECTIVE CABIN PRESSURE MODULE IAW AMM 21-33-01-400-801 WITH NO DEFECTS NOTED. REPLACED PRIMARY OUTFLOW VALVE WITH A NEW IAW AMM 21-32-01-400-801, WITH NO DEFECTS NOTED. REPLACED SECONDARY OUTFLOW VALVE WITH A REPAIRED UNIT IAW AMM 21-32-01-400-801, WITH NO DEFECTS NOTED.