As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) IN THE COURSE OF CONDUCTING THE PRE-FLIGHT CHECK, IT WAS NOTED THAT THE A SYS EMDP WAS NOT ENGAGING. DURING THE TROUBLESHOOTING PROCESS MAINTENANCE FOUND THE GROUND FAULT DETECTOR HAD TRIPPED AND WAS UNABLE TO BE RESET. THE GROUND FAULT DETECTOR WAS SUBSEQUENTLY REPLACED AND TESTED IAW AMM 29-15-06 AND NO FURTHER FAULTS WERE NOTED.