As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT PACK OUTPUT TEMPERATURE APPEARS TO BE WARMER THAN THE RIGHT PACK ON THE GROUND. PERFORMED BITE CHECK ON THE CABIN TEMPERATURE CONTROLLER PER THE FIM WITH NO FAULTS DISPLAYED. PERFORMED BITE CHECK OF LEFT AND RIGHT 35 DEG CONTROLLERS. CONTROLLER FAULT WAS DISPLAYED ON THE LEFT CONTROLLER. REPLACED LEFT 35 DEG CONTROLLER. OPERATIONAL CHECK NORMAL.