What was found
CLT - FLT 858 - ON CLIMB-OUT FROM CLT, THE AIRCRAFT WOULD NOT PRESSURIZE. CAPTAIN COULD NOT CONTROL PRESSURIZATION IN AUTO, STANDBY OR MANUAL MODE. FLIGHT RETURNED TO FIELD AT CLT AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCY WAS DECLARED. MAINTENANCE REMOVED AND REPLACED THE CABIN PRESSURE SELECTOR PANEL PER MM 21-31-00. ALSO, REMOVED AND REPLACED THE CABIN PRESSURE CONTROLLER (P/N 763810-1) AND THE AFT OUTFLOW VALVE (P/N 711003-3). OPS CHECK GOOD. (M)