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Fuel Pump

  1. Ensure battery is fully charged. Ensure fuel pump connector at fuel tank is securely connected. Turn ignition on with engine off. Connect New Generation Star (NGS) scan tool to data link connector 2. Connector is located under left side of instrument panel, right of steering column. Using scan tool, select ACTIVATE COMMAND MODES. Select OUTPUT TEST MODE. Press MODE to change to ALL ON mode. Press start to run fuel pump. Listen for fuel pump operation. Turn relay off.
  2. If fuel pump does not operate, disconnect fuel pump connector at fuel tank. Using DVOM, check continuity between fuel pump power and ground terminals. See Fig 1 . If continuity does not exist, replace fuel pump. If continuity exists, go to next step.
  3. Using NGS scan tool as in step 1), operate fuel pump. Using DVOM, measure voltage between fuel pump wiring harness connector power terminal and chassis ground. Voltage should be more than 10.5 volts. If voltage is as specified, but fuel pump is still inoperative, go to next step. If voltage is not as specified, check fuel pump relay. See FUEL PUMP RELAY heading below. Replay relay as necessary. If relay is okay, check inertia fuel shutoff switch. See INERTIA FUEL SHUTOFF SWITCH heading below.
  4. Disconnect fuel pump connector at fuel tank. Using DVOM, measure resistance between fuel pump ground terminal and chassis ground. Resistance should be less than one ohm. If resistance is not as specified, repair open ground circuit.
Fig 1: Identifying Fuel Pump Terminals
G95A33456Courtesy of MAZDA MOTORS CORP.