What was found
PHX - ABORTED T/O - FLT 484 - ON DEPART ROLL T/O WARNING CONFIG HORN SOUNDED. REPORTED ALL FLT CONTROLS AND CONFIG WERE PROPER FOR T/O. MX R/R`D M983 CIRCUIT CARD. OP CHECKS GOOD IAW BOEING 737-300 MM 32-09-20-4. T/O WARNING TESTS GOOD IAW AMERICA WEST AIRLINES TASK CARD A1B31009. MX NOTED BEFORE REPLACEMENT OF M983 CIRCUIT CARD, USED AN OHMMETER AND MEGGER ON PIN 26-D2596P. WHILE SHAKING/TAPPING WIRING AND ADJACENT AREAS OF FLAP DRUM SWITCH, SPEED BRAKE HANDLE SWITCH, STAB SWITCHES, E3-2 RACK RELAYS & TEST SWITCHES THE MEGGER NEVER WENT TO GROUND. A/C HAS PREVIOUS HISTORY OF ABORTED T/O DUE TO T/O CONFIG HORN. ON 4/7/06, FLT 876, SFO TO LAS, A/C ABORTED T/O FOR CONFIG HORN. CREW APPLIED PRESSURE ON SP