What was found
MAINTENANCE MESSAGE 73-30311 DISPLAYED ON CDU RECENT FAULTS. SHORT TIME FAULT. THE START SWITCH SIGNAL AND BUS DATA DISAGREE. ACFT GROUNDED. ACCOMPLISHMENT OF T/C 78273000 ON WO 306045 SHOWED NO FAULTS ON EITHER ENGINE. PERFORMED T/C FOR FAULT 73-30311, DUAL CHANNEL FAULT FOR NR 1 ENGINE IAW FIM 73-24, TASK 813. INITIAL EVALUATION, EEC TEST IAW MM 73-21-00-700-804-F00 IN EACH START SWITCH POSITION. DID NOT CONFIRM FAULT. PERFORMED START SWITCH TEST FOR NR 1 ENGINE START SWITCH S266 IAW MM 80-11-00-730-801-F00. ALL TESTS PASS.