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Ecu Power Source Circuit

  1. Turn ignition off. Remove tilt and telescopic ECU with wiring harness connector attached. Using a voltmeter, measure voltage by backprobing between rear of 22-pin ECU connector T9 terminal No. 22 (Violet/Yellow wire) and 12-pin ECU connector T8 terminal No. 3 (White/Black wire). See Figure. If voltage is not 10-16 volts, go to next step. If voltage is 10-16 volts, go to next test listed in SYMPTOM DIAGNOSIS  table under TROUBLE SHOOTING.
  2. Using an ohmmeter, measure resistance by backprobing rear of 12-pin ECU connector T8 between terminal No. 3 (White/Black wire) and ground. If resistance is 1000 ohms or less, go to next step. If resistance is more than 1000 ohms, repair or replace wiring harness or connector between tilt and telescopic ECU and ground connection. See WIRING DIAGRAMS .
  3. Check continuity of MPX-B fuse (10-amp) located in engine compartment junction block, near left strut tower. If continuity does not exist, check and repair short in wiring harness between MPX-B 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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