What was found
(CAN) CREW REPORTED THEY COULD NOT START NR 1 ENGINE. THEY HAD FUEL FLOW BUT NO EGT. ACFT RETURN TO GATE. MAINTENANCE FOUND NR 1 ENGINE ELECTRONIC ENGINE CONTROL CHANNEL A ALT POWER BREAKER POPPED AND WILL NOT RESET WHEN ELECTRONIC ENGINE CONTROL POWERED, ADDITIONALLY NR 1 ENGINE LT IGN BREAKER ALSO OUT. ALSO, FOUND NR 1 CTAI VALVE NOT INDICATING CORRECTLY. CB WAS OUT AS WELL IT DID RESET OK, BUT STILL NOT INDICATING NORMALLY. COMMON COMPONENT FOR ALL 3 DEFECTS ARE PYLON DISCONNECT D8056. CONNECTOR INSPECTED AND FOUND ARCING DAMAGE TO PIN 21, 22 AND 23. CONNECTOR D08056 P AND J REPLACED ALL AFFECTED SYSTEM, TESTED SERVICEABLE,