As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKE OFF, THE ACFT DID NOT PRESSURIZE. COMPLIED WITH UNPRESSURIZED FLT, ABNORMAL CHECK LIST3566. ANTI-ICE INDICATION DUE TO PRESSURIZATION PROBLEM. INSPECTED THE AVONICS GROUND COOLING VALVE IAW AMM 21-29-18. FOUND THE VALVE CLOSING MECHANICAL MECHANISM TO BE NOT FULLY CLOSING. COMPLIED WITH M PROCEDURES AS REQUIRED. REACTIVATED AVIONICS COOLING GROUND VALVE.