As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
REF ACTION PLAN 10367 FOR MDDR 52209, 19L1 & 19L2 PDU'S NOT TRANSITIONING WHEN SELECTED TO FWD OR AFT DRIVE POSITIONS. R & R MASTER CONTROL PANEL IAW MM 25-57-09 & PDU`S 19L1 & L2. OPERATIONS OK. HAD TO REMOVE NEW PANEL & REINSTALL ORIGINAL PANEL DUE TO ARCING & CHAFED WIRES BEHIND PANEL. MDDR 52209 REMAINS OPEN.