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Key Unlock Warning Switch Circuit

  1. Remove tilt and telescopic control module and leave harness connectors connected. Insert key into ignition but do not turn ignition on. Measure voltage between tilt and telescopic control module connector T10, terminal No. 10 and ground. See Figure. Voltage should be less than one volt with key in ignition and 10-14 volts with key removed from ignition. If voltage is as specified, go to TROUBLE SHOOTING  and identify next circuit to be checked. If voltage is not as specified, go to next step.
  2. Disconnect key unlock warning switch connector. Measure resistance between key unlock warning switch connector terminals No. 9 and No. 10. See Fig 1. Resistance should be more than 1 megaohm with key removed from ignition switch. Continuity should exist with key inserted in ignition. If resistance is as specified, go to next step. If resistance is not as specified, replace key unlock warning switch and retest system.
  3. Check wiring harness between tilt and telescopic control module and key unlock warning switch. See WIRING DIAGRAMS . If wiring harness is okay, replace tilt and telescopic control module and retest system.
Fig 1: Testing Key Unlock Warning Switch
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