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Tachometer Inoperative

  1. Turn ignition switch to OFF position. Disconnect Ignition Control Module (ICM) connector. Plug Instrument Panel Tester (J-33431) into a wall outlet. Connect Harness Adapter (J-33431-10) to instrument panel tester. Connect Black lead of harness adapter to ground, and Red lead to ICM harness connector terminal "E" (White wire). Move instrument panel tester to 54 MPH, 60 Hz and turn power switch to ON position. Turn ignition switch to RUN position. If tachometer reads about 1350 RPM, go to next step. If tachometer does not read about 1350 RPM, go to step 3).
  2. Check for poor terminal contacts at ICM connector. Repair as necessary and recheck system operation. If contacts are okay, replace Ignition Control Module (ICM). Recheck system operation.
  3. Check for open or short to ground in circuit No. 121 (White wire) between ICM and instrument cluster Orange 32-pin connector C2, terminal E8. See Figure . Check for poor terminal contact at Black 8-pin connector C107 (engine-to-ignition wiring harness, located at right front of engine near ignition coils), terminal "E" (White wire). Check for poor terminal contact at Black 66-pin connector C101 (body-to-engine wiring harness, located at right rear of engine compartment, near strut tower), terminal J7 (White wire). Check for poor terminal contact at instrument cluster connector C2, terminal E8 (White wire). Repair as necessary and recheck system operation. If circuits and connections are okay, replace instrument cluster. See INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. Recheck system operation.
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