As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED A LEFT BLEED AIR DUCT WARNING ON DEPARTURE. THE AIRCRAFT RETURNED TO FIELD LANDING WITHOUT INCIDENT. MAINTENANCE INSPECTED, REMOVED, REPLACED, AND OPERATION CHECKED LOOP MT137. ALL WORK WAS ACCOMPLISHED USING THE AIRCRAFT MANUALS. AIRCRAFT RELEASED FOR SERVICE.