What was found
5 OUT OF 6 FORWARD LOWER CARGO DOOR SILL AREA LIGHTS DO NOT ILLUMINATE DURING CARGO LOADING OPERATIONS. AT THE FORWARD UPPER SILL LIGHT POSITION, SMOKE WAS FOUND AT A BURNED WIRE. THE FORWARD UPPER LIGHT ASSEMBLY WAS REMOVED AND FOUND 4 WIRES BURNED, 2 SHORTED TOGETHER, AND 2 TERMINAL ENDS WERE BURNED OFF. ALSO, FOUND CIRCUIT BREAKER C21, TERMINAL 2 BURNED. THE CORRECTIVE ACTION ACCOMPLISHED WAS REMOVING & REPAIRING THE BURNED WIRING, REPLACING THE TERMINALS, AND REPLACING THE FORWARD CARGO COMPARTMENT LIGHTS TRANSFORMER T148. THE SUSPECTED CAUSE OF THE INOPERATIVE LIGHTS AND BURNED WIRING IS A FAULTY TRANSFORMER T148.