As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CABIN PRSS CAUTION AT FL 180, EXTINGUISHED ON DESCENT. AIRCRAFT PRESSURIZED WE THOUGHT, BUT MAYBE IT DIDNT. CABIN AND FLT CPT HOT LIGHTS ON AS WELL. REMOVED FROM SERVICE. REF W/O 327859 FOR REPLACEMENT OF #1 HP VALVE, OPS CHECKS OF TEMP CONTROL AND PRESSURIZATION AND OTHER WORK PEFORMED. RETURNED TO SERVICE.