What was found
WHILE PERFORMING T/C 78273000, THE NR 1 ENGINE LOGGED SHORT TERM FAULT CODE 73-30311, THE START SWITCH SIGNAL AND ARINC BUSS DATA DISAGREE ON EVERY LEG. ACFT GROUNDED. PERFORMED FIM 73-24, TASK 813 INITIAL EVALUATION. EEC TEST IAW AMM 73-21-00 FAILED FOR SAME FAULT WITH START SWITCH IN THE OFF POSITION. EXERCISED START SWITCH SEVERAL TIMES BY REPEATEDLY SELECTING EACH DETENT. CONTINUED WITH FIM FAULT ISOLATION FOR DUAL CHANNEL FAULT. THE START SWITCH CDS DEU DISCRETE STATUS AGREED WITH VALUES IN TABLE 215. REPEATED EEC TEST WITH START SWITCH IN OFF, GROUND, CONT, AND FLT POSITIONS. ALL TESTS PASSED. NO FAULTS NOTED.