Key Unlock Warning Switch Circuit
- Turn ignition off. Remove tilt and telescopic ECU with wiring harness connector attached. Using a voltmeter, measure voltage by backprobing rear of 18-pin ECU connector T10 between terminal No. 10 (Yellow wire) and ground. See Figure. With key removed from ignition key cylinder, voltage should be 10-14 volts. With key inserted in ignition key cylinder, voltage should be less than one volt. 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.
- Disconnect 11-pin key unlock warning switch connector. Using an ohmmeter, measure resistance between key unlock warning switch connector terminals No. 10 (Yellow wire) and No. 9 (White/Black wire). See Fig 1. With key removed from ignition key cylinder, resistance should be one megohm or more. With key inserted in ignition key cylinder, continuity should exist between terminals. If resistance is as specified, go to next step. If resistance is not as specified, replace key unlock warning switch and retest system operation.
- Check wiring harness and connectors between tilt and telescopic ECU and key unlock warning switch. See WIRING DIAGRAMS . Repair or replace as necessary. If wiring harness and connectors are okay, check tilt and telescopic ECU. See TILT & TELESCOPIC ECU PIN VOLTAGE TESTS under COMPONENT TESTS. Replace tilt and telescopic ECU as necessary and retest system operation.
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