Key Unlock Warning Switch Circuit
- Turn ignition off. Remove tilt and power telescopic ECU with wiring harness connector attached. Measure voltage between ground and by backprobing rear of terminal No. 10 (Yellow wire) at 18-pin ECU harness connector T10. See Figure. If battery voltage exists with key removed from ignition key cylinder and voltage is less than one volt with key inserted in ignition key cylinder, go to next test listed in SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING. If voltage is not as specified, go to next step.
- Turn ignition off. Disconnect 11-pin key unlock warning switch harness connector. Using an ohmmeter, measure resistance between terminals No. 10 (Yellow wire) and No. 9 (White/Black wire) at key unlock warning switch harness connector. See Fig 1. If resistance is one megohm or more with key removed from ignition key cylinder and continuity exists between terminals with key inserted in ignition key cylinder, 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 power 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 power telescopic ECU. See TILT & TELESCOPIC ECU PIN VOLTAGE TESTS under COMPONENT TESTS. Replace tilt and power telescopic ECU as necessary and retest system operation.
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