What was found
CREW RECEIVED LEFT BLEED DUCT WARNING MESSAGE DURING CLIMBOUT. CREW PERFORMED QRH, RETURNED TO FIELD AND LANDED WITHOUT INCIDENT. WARNING MESSAGE EXTINGUISHED SEVERAL MINUTES AFTER QRH WAS RUN. MAINTENANCE TROUBLESHOT LEFT BLEED WARNING AND REMOVED AND REPLACED AILC (ANTI-ICE AND LEAK DETECTION CONTROLLER) DUE TO BEING UNABLE TO READ EVENT LOCATION HISTORY FROM AILC. MAINTENANCE CLEANED AND REPOSITIONED TWO (2) LEFT BLEED LOOPS DUE TO HIGH RESISTANCE AND PERFORMED CHECKS USING AIRCRAFT MAINTENANCE MANUALS. AIRCRAFT RELEASED FOR SERVICE.