What was found
NR 1 PITCH TRIM TRIPPED BEFORE TAXI. ALL COCKPIT LIGHTS STARTED FLASHING WITH POWER-UP FOR TAXI. LOST VSI INDICATORS TEMPORARILY. LOST TAWS INDICATIONS. FOUND NR 1 GCU CAUSING POWER INTERRUPTIONS. R/R NR 1 GCU AND DISCONNECTED NR 2 CSD, OPS CK GOOD IAW AMM CHAPTER 22-12-34. (2) R/R NR 1 GCU AND DISCONNECTED NR 2 CSD, OPS CK GOOD IAW AMM CHAPTER 24-21-12.(3) R/R NR 1 GCU AND DISCONNECTED NR 2 CSD, OPS CK GOOD IAW AMM CHAPTER 34-11-50. R/R NR 1 GCU AND DISCONNECTED NR 2 CSD, OPS CK GOOD IAW CMM ST3400. WHILE T/S ITEMS NR 1 THRU NR 4, FOUND NR 2 ENGINE GCU FAULTY. R/R NR 2 ENGINE GCU. CSD RECONNECTED, OPS CHECKS GOOD IAW AMM CHAPTER 24-21-12. DMI NR 7005 CLEARED. (STATUS:SUPP/CLOSED)