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Test No. 1: Power Source Circuit

  1. Check condition of MPX-B and DOOR fuses located in driver-side and passenger-side junction blocks. If fuses are okay, go to next step. If fuse(s) are faulty, replace appropriate fuse and retest system operation.
  2. Turn ignition off. Disconnect body ECU connector. Measure voltage between the following ECU connector terminals.
    • Terminal No. 2 (BECU) and White/Black wire (GND).
    • Terminal No. 1 (BSUB) and White/Black wire (GND).

    If voltages are not 10-14 volts, go to next step. If voltages are 10-14 volts, system is okay.

  3. Check wiring and connectors between body ECU and ground, and between body ECU and battery. Repair wiring as necessary.
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