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Ignition Switch Circuit

  1. Turn ignition off. Remove tilt and telescopic ECU with wiring harness connector attached. Using a voltmeter, measure voltage by backprobing rear of 12-pin ECU connector T9 between terminal No. 1 (Black/Red wire) and ground. See Figure. With ignition off, voltage should be less than one volt. Turn ignition on. Voltage should be 10-14 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to next test listed in SYMPTOM DIAGNOSIS  table under TROUBLE SHOOTING.
  2. Turn ignition off. Check continuity of ECU-IG fuse (15-amp) located in instrument panel junction block, behind left kick panel. If continuity does not exist, check and repair short in wiring harness between ECU-IG fuse and all components connected to fuse. See WIRING DIAGRAMS . If continuity exists, check for open in wiring harness between tilt and telescopic ECU and battery. Repair or replace as necessary and retest system operation.
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