What was found
ACFT PERFORMED AN UNSCHEDULED LANDING DUE TO PRESSURIZATION FAILURE, AFTER 45 MIN OF USING ANTI-ICE, AT 350 FLT LEVEL, FLOW & CABIN ALT LIGHT TURNED ON. CAPTAIN ACCOMPLISHED THE ABNORMAL PROCEDURE & PERFORMED AN UNSCHEDULED LANDING. DURING REVISION OXYGEN GENS DETECTED ACTIVED, WINGS & TAIL ANTI-ICE VALVES OPS TESTED CORRECT. PRESSURIZATION & ANTI-ICE TEST PERFORMED IN MANUAL AND AUTO MODE IAW MM. THE OXYGEN GENS DEFERRED & ACFT FLEW TO MEX. DURING OVERNIGHT CHECK, PRESSURIZATION & ANTI-ICE TEST WERE PERFORMED IN MANUAL AND AUTO MODE IAW MM, OXYGEN GENS REPLACED IAW MM & WING ANTI-ICE VALVE REPLACED IAW MM, TESTED CORRECT. DEFERRED REPORT WAS CLOSED.