As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A/C CABIN ALTITUTE CLIMBED ABOVE 10,000 FT WHEN CLIMBING THRU FL 27,000. PRESSURIZATION CONTROL WAS REGAINED AFTER SELECTING MAN DC MODE. REPLACED CABIN PRESSURE CONTROLLER IAW 21-31-21 PG 401, TT 0099110. ALSO, OUTFLOW VALVE WAS REPLACED (SEE LP 7558125 & 7558124) TT 0101252.