What was found
AIRCRAFT LANDED BACK MMTO, MEXICO DUE TO PRESSURIZATION PROBLEM. CABIN AIR CONDITIONING VALVE BAD, VERIFIED VALVE IN THE OPEN POSITION PER MEL 21-12. AIRCRAFT OPS CHECKED GOOD IN BOTH AUTO AND MANUAL. (X)
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
AIRCRAFT LANDED BACK MMTO, MEXICO DUE TO PRESSURIZATION PROBLEM. CABIN AIR CONDITIONING VALVE BAD, VERIFIED VALVE IN THE OPEN POSITION PER MEL 21-12. AIRCRAFT OPS CHECKED GOOD IN BOTH AUTO AND MANUAL. (X)