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Fuel Pump Relay

  1. If fuel pump fails to operate, ensure battery voltage exists on Red and Red/White wires of fuel pump relay and that the fuel pump fuse is okay. If no voltage exists, check power circuits and ground circuits for MCU. MCU controls fuel pump relay ground circuit. See MOTRONIC CONTROL UNIT (MCU) in this article.
  2. If battery voltage exists at fuel pump relay, note wire color and location on fuel pump relay terminals. Apply battery voltage to Red and Red/White wire terminals of relay. Ground the Brown/Green wire terminal. Voltage should now exist at Green/Violet wire terminal of the relay. Replace relay if voltage does not exist.