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Body No. 4 Ecu Power Source Circuit

  1. Check condition of MPX-B3 and LUG J/B fuses. See FUSE LOCATIONS (BODY NO. 4 ECU)  table. If fuses are okay, go to next step. If fuse(s) are faulty, replace appropriate fuse and retest system operation.
  2. Disconnect body No. 4 ECU connector. Measure voltage between body No. 4 ECU connector terminal GND and terminals MPX-B and HIC. See PIN VOLTAGE TESTS . Turn ignition off. If 10-14 volts are not present, go to next step. If 10-14 volts are present, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING .
  3. Check wiring between body No. 4 ECU and ground. Repair wiring as necessary. If wiring is okay, check wiring between body No. 4 ECU and battery. Repair as necessary.
FUSE LOCATIONS (BODY NO. 4 ECU)

Fuse Location
LUG J/B Right Side Of Engine Compartment In Fuse/Relay Block
MPX-B3 Passenger-Side Junction Block