As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UNABLE TO MAINTAIN CABIN PRESS WITH FLOWS AT MAX MANUAL CONTROL FULL CLOSED. FOUND FAULTY SCOOP ANTI-ICE SWITCH CAUSING LT SCOOP VALVE TO INTERMITTINGLY STICK IN THE OPEN POSITION. REPLACED SWITCH PER MM 20-50-1. ALSO REPLACED LT SCOOP VALVE AS PRECAUTION PER MM 30-20-2. OPS CK GOOD. OK FOR SERVICE.