As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CABIN WOULD NOT PRESSURIZE AT FL010 WHEN ALARM WENT OFF DURING TAKE OFF. CA SWITCHED FROM CONTROLLER 1 TO 2. STARTED WORKING ON WAY TO LAND. FLAGGED SDR PFR SHOWS SDAC2:NO CPC1 ANALOG SIGNAL. ADDED PHOTO OF PFR. REPLACED OUTFLOW VALVE IN REFERENCE TO AMM 21-31-51-400-001-A. OPS CHECK GOOD PARTS USED: 31-2131-9-9001,QTY :1 ROTABLE PARTS CHANGE WAS INDICATED - TT # 1543794 SN OFF 1606 / VALVE, OUTFLOW OFF 31-2131-9-9001 1606 ON 31-2131-9-9001 1617