What was found
F/A REPORTS A BURNING SMELL COMING FROM THE REAR CABIN AFTER TAXIING IN TO THE GATE. REMOVED FROM SERVICE. PERFORMED FIM TASK FOR UNUSUAL ELECTRICAL FUMES, REF Q400 FIM 21-22-01-810-801. NO DEFECTS NOTED. PERFORMED OPS TEST OF ECS TEMP CONTROL IAW Q400 AMM 21-61-00-710-803. NO ABNORMAL SMELLS NOTED. RAN BOTH ENGINES WITH CABIN AND FLT COMP TEMPS AT MAX HEAT. NO ABNORMAL SMELLS NOTED. IT WAS REPORTED THAT A PASSENGER CLAIMED TO HAVE AN ITEM IN THEIR BAG THEY MAY HAVE PRODUCED THE SMELL. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.