What was found
ATB DUE TO ELECTRICAL PWR FAIL IN FLT WITH THE FOLLOWING C/B POPPED ON P-6 PANEL-DC STBY-BAT BUS DIST-L GEN CONT UNIT-RAT MANUAL AND THE ASSOCIATED ALERTS. BPCU BITE FAULTED LT GCU CODE 24-30101 PER FIM. REPLACED LT GCU, GROUND TEST OK PER FIM USING WDM ISOLATED, VISUALLY INSP SHOOK DOWN AND MEGGED ALL RELATED WIRING TO THE FOUR POPPED C/B. NO SHORTS OR WIRING DAMAGE FOUND. INSP WIRING HARNESS IN P6 PANEL AND AB INSP CARD FILES FOR CHAFING, NONE FOUND. REPLACED STBY PWR RELAY K 109 STBY PWR CB A2 AND MAIN BATT CHGR DEPLOYED STOWED RAT SEVERAL TIMES TO VERIFY NML OPS RAN BOTH.