What was found
WHILE PERFORMING T/C 78273000 FOUND LONG TIME FAULT 77-20871 THE TOP LEFT EGT SIGNAL (T495S4) IS OUT OF RANGE ENGINE 1. GROUNDED - YES. #1 ENG INPUT MONITORING: S1 266.65, S2 257.70, S3 339.71, S4 224.83. S2, S3 DELTA OUT OF LIMITS. ACCOMPLISHED EGT SYSTEM INSPECTION REF AMM 77-22-01-200-801. J10 HARNESS FAILS RESISTANCE CHECK. CJ10 HARNESS AND LEFT T49.5 PROBES OK. ALSO CHECKED J9, CJ9 AND RIGHT T49.5 PROBES, ALL OK. REMOVED AND REPLACED J10 HARNESS REF AMM 73-21-06-400-802-F00. ACCOMPLISHED EEC TEST PER AMM 73-21-00 AND TEST 12 ACTUATORS TEST PER AMM 71-00-00-00. OPS CK GOOD. ACCOMPLISHED IDENT/CONFIG REF AMM 73-21-00 AND EEC DISCRETES TEST, REF AMM 73-21-00. FINAL T49.5 SYSTEM TEMPS: S1-104.87, S2-97.13, S3-97.39, S4-108.73. ETOPS SIGNIFICANT SYSTEM GROUND VERIFICATION SUCCESSFUL. ACCOMPLISHED POWER ASSURANCE REF AMM 71-00-00-700-813-F00, CKS GOOD.