As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ACFT CLLIMBED TO FL 260. CREW NOTICED A DISCREPANCY IN THE CABIN PRESSURE DIFFERENTIAL, ALTITUDE AND CONTROLLER INDICATION. AFTER INVESTIGATION AND COMPARISON WITH ANOTHER ACFT, IT WAS FOUND DURING OVERHAUL THE INCORRECT FACE HAD BEEN INSTALLED ON THE RATE CONTROLLER.