As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AUTO PRESSURIZATION SYSTEM FAILED ELEVATION DIGITS DISSAPEARED AND CABIN ALTITUDE RAPIDLY DESCENDED TO DASHES ON CABIN ALTITUDE. AUTO PRESSURE DEFERRED PER MEL 21-17 SECTION 4 M PROCEDUES C/W. REMOVED AND REPLACED MANUAL PRESSURE CONTROL RECEPTACLE IAW EMB MM 21-31-02 OPS CHECK GOOD IAW MM 21-30-00 PERFORMED OPC PRESURUZATION CONTROL IN AUTO/MANUAL MODE IAW AMM 21-31-00.OPC GOOD MEL 21-17 RESTORED.OUTFLOW VALVE SECTION 4 PROCEDURE REACTIVATED.