As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FWD CABIN TEMP CONTROL COMPLETELY ERRATIC IN AUTO MODE. SLIGHTEST ADJUSTMENT RESULTS IN INSTANT FULL SCALE TEMP CHANGE. IMPOSSIBLE TO CONTROL. SWITCH PLACED IN OFF. ACFT GROUNDED. FOUND DEBRIS IN THE SENSOR FAN. CLEANED SENSOR FAN, OPS CK NORMAL. BITE CK NO FAULTS.