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Ecu Power Source Circuit

  1. Check condition of DOME fuse. DOME fuse is located in engine compartment junction block, on left side of engine compartment. If fuse is okay, go to next step. If fuse is faulty, check for short in circuit between fuse and anti-theft/door lock control ECU. See WIRING DIAGRAMS . Repair short in harness or connectors as necessary. Replace fuse and retest system operation.
  2. Turn ignition off. Disconnect anti-theft/door lock control ECU connectors T7 and T8. Turn ignition on. Using a voltmeter, measure voltage between ECU 25-pin connector T8 terminal No. 1 (Red wire) and ECU 9-pin connector T7 terminal No. 4 (White/Black wire). See Figure. See WIRING DIAGRAMS . If voltage is not 10-14 volts, go to next step. If voltage is 10-14 volts, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING .
  3. Check circuits for faults between body ground and anti-theft/door lock control ECU. See WIRING DIAGRAMS . Repair or replace as necessary. If circuits are okay, check and repair circuits between body control ECU and battery. Retest system operation.
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