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Ecu Power Source Circuit No. 2

NOTE: Body control ECU No. 2 is plugged into driver-side junction block. To check voltages, it is necessary to probe wiring going into junction block. See Fig 1.
  1. Check condition of MPX-B and GAUGE fuse. 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 Black/Yellow wire (IG) and White/Black wire (GND) leading into junction block. See Fig 1. If voltages are not 10-14 volts, go to next step. If voltages are 10-14 volts, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING .
  3. Turn ignition off. Disconnect body control ECU No. 2 connector (located behind driver left side kick panel). Turn ignition on. Using a voltmeter, measure voltage between Green/White wire (BECU) and White/Black wire (GND) leading into junction block. If voltages are not 10-14 volts, go to next step. If voltages are 10-14 volts, 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 No. 2. See WIRING DIAGRAMS . Repair or replace as necessary. If circuits are okay, check and repair circuits between body control ECU No. 2 and battery. Retest system operation.
Fig 1: Identifying Driver-Side Junction Block Terminals
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