As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE IN CRUISE, PILOTS SAY THE CABIN PRESSURE INDICATOR STOP WORKING. CREW THEN SMELLED A FAINT ELECTRICAL BURNING SMELL, NO SMOKE WAS REPORTED. ACFT RETURNED, NO OTHER PROBLEMS WERE NOTED. MX FOUND THAT THE CABIN PRESSURE CONTROLLER HAD FAILED AND WAS THE SOURCE OF THE ELECTRICAL BURNING SMELL.