What was found
ON CLIMB-OUT, UPPER FUSELAGE ANTI-COLLISION LIGHT FELL OUT OF MOUNT AND CAUSED POWER WIRES TO SHORT, WITH RESULTING SPARKS AND SMOKE IN CABIN. FLT RETURNED TO CAE. FOUND DAMAGED WIRES ON LIGHT ASSEMBLY. REMOVED ASSEMBLY, SECURED WIRES, PLACED ON MCO. LIGHT ASSEMBLY WAS REPLACED, OPERATION NORMAL.