What was found
(CAN) ELECTRICAL SHORT IN ARCDU NR 2 ON THE GROUND AFTER SHUTDOWN RESULTING IN SIGNIFICANT SMOKE IN THE FLIGHT COMPARTMENT, EMANATING FROM THE NR 2 ARCDU. ON INSPECTION FOUND NR 2 ARCDU CIRCUIT BREAKER TRIPPED. NR 2 ARCDU REPLACED IAW AMM 23-81-01. WHEN ACFT REPOWERED FOUND NR 1 STARTER ENGAGED. SUSPECT ELECTRICAL SPIKE AS CAUSE NR 1 DC GENERATOR CONTROL UNIT REPLACED IAW AMM 24-31-06. ALL OTHER SYSTEMS REPORTED AS FALLING OFF LINE CHECKED AND FOUND SERVICEABLE.