As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURN BACK ONCE AIRBORNE F/D, U/D & C/R TEMP UNCONTROLLABLE IN AUTO OR MANUAL MODE. NO MAGENTA REF. TEMP SETTINGS WERE DISPLAYED. TEMP IN F/D VARIED FROM 63F TO 87F. CREW REST DROPPED TO 50F. ATB ACCOMPLISHED. SEE BARCODE T3F18E008JN5Z. R AND R UD TRIM AIR VALVE IAW AMM 21-61-10. OPS CHECK GOOD.