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Body Control Ecu Power Source Circuit

  1. Check condition of WIPER, RADIO NO. 2, D FR DOOR, P FR DOOR, and GAUGE fuses. See FUSE LOCATIONS  table. If fuses are okay, go to next step. If fuse(s) are faulty, replace appropriate fuse and retest system operation.
  2. Turn ignition on. Using a voltmeter, measure voltage between the following body ECU harness connector terminals. See Figure.
    • Connector B5, terminal No. 8 (WIG) and connector B8, terminal No. 15 (GND).
    • Connector B6, terminal No. 2 (ACC) and connector B8, terminal No. 15 (GND).
    • Connector B6, terminal No. 9 (SIG) and connector B8, terminal No. 15 (GND).
    • Connector B5, terminal No. 8 (WIG) and connector B5, terminal No. 20 (GND2).
    • Connector B6, terminal No. 2 (ACC) and connector B5, terminal No. 20 (GND2).
    • Connector B6, terminal No. 9 (SIG) and connector B5, terminal No. 20 (GND2).

    If battery voltage does not exist, go to next step. If battery voltage exists, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING .

  3. Turn ignition off. Disconnect body control ECU connector (located under left side of instrument panel). Turn ignition on. Using a voltmeter, measure voltage between the following body control ECU harness connector terminals.
    • Connector B8, terminal No. 1 (BDR) and connector B8, terminal No. 15 (GND).
    • Connector B8, terminal No. 6 (BECU) and connector B8, terminal No. 15 (GND).
    • Connector B8, terminal No. 1 (BDR) and connector B5, terminal No. 20 (GND2).
    • Connector B8, terminal No. 6 (BECU) and connector B5, terminal No. 20 (GND2).

    If battery voltage does not exist, go to next step. If battery voltage exists, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING .

  4. Check circuits for faults between body ground and body 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.
FUSE LOCATIONS

Fuse Location
D FR DOOR (1) Fuse Holder
GAUGE (2) Instrument Panel Junction Block
P FR DOOR (1) Fuse Holder
RADIO NO. 2 (2) Instrument Panel Junction Block
WIPER (2) Instrument Panel Junction Block
(1) Located behind driver left side kick panel.
(2) Located under left side of instrument panel.
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