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Body No. 3 Ecu Power Source Circuit

  1. Check condition of MPX-IG, MPX-B1, WIP and P B/ANC fuses. See FUSE LOCATIONS (BODY NO. 3 ECU)  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. Measure voltage between passenger-side junction block terminal GND and terminals MPX-IG and ACC. See PIN VOLTAGE TESTS . Turn ignition off. Disconnect passenger-side junction block connector. Measure voltage between passenger-side junction block connector terminal GND and terminals MPX-B, WIP and P B/ANC. If 10-14 volts are present, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING . If 10-14 volts are not present, check wiring between body No. 3 ECU and ground. Repair wiring as necessary. If wiring is okay, go to next test listed in BODY NO. 3 CONTROL SYSTEM  table under TROUBLE SHOOTING .
FUSE LOCATIONS (BODY NO. 3 ECU)

Fuse Location
P B/ANC Passenger-Side Junction Block
MPX-B1 Passenger-Side Junction Block
MPX-IG Driver-Side Junction Block
WIP Engine Room Junction Block