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Fuel Pump Relay

  1. Disconnect negative battery cable. Remove Powertrain Control Module (PCM) harness connector. Reconnect battery cable. Turn ignition on. Check for voltage at Dark Blue/Yellow wire in PCM harness connector. If voltage is not present, go to step 4). If voltage is present, ground the wire. Fuel pump should work.
  2. If fuel pump does not work, check if relay clicks. If relay does not click, go to step 5). If relay clicks, ensure voltage is present at relay terminals No. 30 (battery) and 87 (fuel pump), and at fuel pump. See Fig 1 .
  3. If fuel pump still does not work, check fuel pump ground. If ballast resistor and ground are okay, replace fuel pump.
  4. If no voltage is present, ensure wire has continuity to fuel pump relay terminal No. 85. Ensure voltage (from ignition switch) is present at relay terminal No. 86. See Fig 1 .
  5. If all circuits are okay or fuel pump relay did not click in step 2), check resistance between relay terminals No. 86 and 85. See Fig 1 . Resistance should be 70-80 ohms. If resistance is not 70-80 ohms, replace relay.
  6. Disconnect negative battery terminal. Reconnect PCM harness connector. Connect battery cable. Check fuel pump operation. If fuel pump does not operate, see TESTS W/CODES - 2.5L & 4.0L article in this section and check PCM.
Fig 1: Identifying Fuel Pump Relay Terminals
G91D13972Courtesy of CHRYSLER CORP.