What was found
FA/PASSENGERS CALLED COCKPIT FOR BURNING SMELL IN CABIN ON TAXI. NO SMOKE NOTED. CAPTAIN AND FO SMELLED BURNING IN FLT DECK, NO SMOKE NOTED. RAN QRH PROCEDURE, GOT A/C IN SAFE STATE. RAN BOTH PACKS OF APU AND ENGINE BLEEDS, CHECKED FOR SMELLS AND SMOKE, NONE NOTED. TAXIRD A/C AND CHECKED BRAKES AND STEERING FOR DEFECTS, NONE NOTED, OK FOR SERVICE