As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN)PRIOR TO FIRST FLIGHT OF THE DAY, BOTH ENGINES WERE STARTED AND #1 GENERATOR WOULD NOT COME ON LINE AND THE #2 START LIGHT WAS ILLUMINATING INTERMITTENTLY AND DIMLY. #2 STARTER RELAY WAS REPLACED AND ALL PROBLEMS WERE RECTIFIED. MOISTURE AND CORROSION WERE FOUND INSIDE EVEN THOUGH THE ELECTRICAL BOX WAS DRY.