As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF FROM DTW, FLIGHT 2755, SELECTED THE LP BLEED ON AND HAD A LT DUCT OVERTEMP LIGHT WITH A LT BLD CIGED. ORH COMPLETED. RESET AND DUCT OVERTEMP LT RE-ILLUMINATED. L HP WAS OFF AS WELL AS TEMP SELECT IN AUTO POSITION. AIR RETURN TO DTW. MAINTENANCE REPLACED TEMP SENSOR.