What was found
(CAN) SMOKE ODOR IN CABIN IN INITIAL CRUISE. ACFT DIVERTED FOR INVESTIGATION. POWER CONTROL BOARD FOUND BURNED. AFFECTED SEAT AND OTHERS, AS A PRECAUTION, PUT ON MEL. ON A SUBSEQUENT FLIGHT THE CHIMES WERE GOING OFF AGAIN SO DUE TO HISTORY OF CHIMES AND BURNED PCBS, THE ACFT WAS GROUNDED AND STRIPPED TO FIND A CHAFED WIRE IN THE CALL SYSTEM. REPAIR CARRIED OUT IAW SWPM 20-41-20, NEW PCBS INSTALLED AND SYSTEM TESTED SERVICEABLE IAW AMM 33-20-02-04.