As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MESSAGE IN FLIGHT, QRH COMPLIED WITH. DISPLAY COOL MESSAGE INTERMITTENT IN FLIGHT. ALT POSITION WENT TO STANDBY POSITION THEN EXTINGUISHED THRU FL270 THEN WENT OFF (AIR RETURN). UPON INSPECTION FOUND DUCT ABOVE CAPTAINS RUDDER PEDAL OFF. RESECURED DUCT. OPS CHECK GOOD IAW AMM21-24-22.