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No Fuel Pressure

  1. Turn ignition off. Check if Inertia Fuel Shutoff (IFS) switch has been tripped. IFS switch is located inside of trunk area below left side of floor mat. Reset IFS switch if tripped. Repeat FUEL PRESSURE CHECK. If IFS switch is okay, connect Data Link Connector (DLC) fuel pump test terminal to ground terminal using jumper wire. See Figure . Disconnect fuel pump connector at fuel pump. Measure voltage at Black/White wire at fuel pump connector. If voltage is not 10-14 volts, go to next step. If voltage is 10-14 volts, go step 8).
  2. Turn ignition off. Remove fuel pump relay. Relay is located in engine compartment fuse box. Disconnect Powertrain Control Module (PCM). Ensure fuel pump is disconnected. Measure voltage between ground, and Light Green and White/Yellow wires at fuel pump relay connector. If resistances are 10,000 ohms or more, go to next step. If resistances are less than 10,000 ohms, repair short in wires as necessary.
  3. Turn ignition off. Ensure fuel pump relay is disconnected. Turn ignition on. Check for battery voltage at Red/Black wire of fuel pump relay connector. If voltage is as specified, go to next step. If voltage is not as specified, proceed to CIRCUIT TEST VPWR in TESTS W/CODES - EEC 2.5L article in the ENGINE PERFORMANCE section. If VPWR circuit is okay, repair open in Red/Black wire.
  4. Apply battery voltage between terminals "A" and "B" of fuel pump relay. See Fig 1 . Measure resistance between terminals "C" and "D". Resistance should be less than 5 ohms. With no battery voltage applied to relay, resistance between terminals "C" and "D" should be more than 10,000 ohms. If resistance is not as specified, replace relay. If resistance is as specified, go to next step.
    Fig 1: Testing Fuel Pump Relay (2.5L)
    G93E40174Courtesy of FORD MOTOR CO.
  5. Turn ignition off. Ensure fuel pump relay and PCM are disconnected. Install Breakout Box (007-00033). Measure resistance between test pin No. 52B of breakout box and Light Green wire at fuel pump relay. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open Light Green wire between fuel pump relay and PCM.
  6. Check IFS switch. See INERTIA FUEL SHUTOFF (IFS) SWITCH under ENGINE SENSORS & SWITCHES. Replace IFS switch if defective. If switch is okay, go to next step.
  7. Ensure ignition is off and fuel pump relay is disconnected. Disconnect IFS switch connector. Measure resistance of White/Yellow wire between IFS switch connector and fuel pump relay connector. If resistance is less than 5 ohms, repair open wire between IFS switch and fuel pump. If resistance is 5 ohms or more, repair open White/Yellow wire between IFS switch and fuel pump relay.
  8. If voltage was 10-14 volts in step 1), turn ignition off. Disconnect fuel pump connector. Measure resistance between ground and Black wire at fuel pump connector. If resistance is less than 5 ohms, replace fuel pump. If resistance is 5 ohms or more, repair open ground wire.
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