What was found
DURING TAXI, CREW NOTED NR 1 AC BUS TIE LOCKED OUT. CREW ELECTED TO RETURN TO GATE FOR MAINTENANCE TROUBLESHOOTING. AIRCRAFT TAXIED TO GATE WITHOUT FURTHER INCIDENT. MAINTENANCE TROUBLESHOOTING DETERMINED THAT WIRE NR 3-16BL WAS SHORTED TO GROUND, BETWEEN GCU CONNECTOR (FRM13A) AND NR 8 PIN OF IDG CANNON PLUG. REPLACED SHORTED WIRE. OPS CHECKS PERFORMED WITH NO FAULT FOUND. AIRCRAFT RETURNED TO SERVICE. (W)