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Ignition Switch Circuit

  1. Check condition of CIG and ECU-IG fuses located in instrument panel junction block, under left side of instrument panel. If fuses are okay, go to next step. If fuse(s) are faulty, check for short in circuit between fuse(s), ignition switch and anti-theft ECU. See WIRING DIAGRAMS . Repair short in harness or connectors as necessary. Replace appropriate fuse and retest system operation.
  2. Turn ignition off. Disconnect anti-theft ECU connectors T3 and T4. Turn ignition on. Using a voltmeter, measure voltage between ECU 22-pin connector T4 terminal No. 13 (Black/Red wire) and body ground. See Figure. See WIRING DIAGRAMS . If voltages are 10-14 volts, go to next step. If voltages are not 10-14 volts, repair or replace wire harness and connectors between battery and anti-theft ECU.
  3. Check anti-theft ECU pin voltages. See ANTI-THEFT ECU PIN VOLTAGE TESTS  under COMPONENT TESTS. Replace components as necessary and retest system operation.
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