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Home >> Infiniti >> 1993 >> Q45 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Fuel System >> Fuel Delivery >> Fuel Pump Control System Wiring (J30)
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Fuel Pump Control System Wiring (J30)

  1. Unplug fuel pump relay. Turn ignition switch on. Check for battery voltage at fuel pump relay connector terminals No. 2 (Red/Green wire) and No. 3 (Light Green wire). See Figure . If battery voltage is present at terminals No. 2 and 3, go to next step. If battery voltage is not present, check wiring connectors, 7.5-amp fuse in interior fuse box and 15-amp fuse in relay block.
  2. Disconnect fuel pump harness connector. Check continuity of Yellow/Black wire between fuel pump relay and fuel pump. Check continuity of Black/Red wire between fuel pump relay and ECM connector terminal No. 18. See Fig 1 or Fig 2 . Repair wiring as necessary.
  3. If no faults are found in wiring, test fuel pump relay. See RELAYS  under RELAYS & SOLENOIDS. Also test fuel pump and inspect ECM connector pin terminals.
Fig 1: Identifying ECM Terminals (G20)
G93E78554Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 2: Identifying ECM Terminals (J30 & Q45)
G93F78555Courtesy of NISSAN MOTOR CO., U.S.A.