312C, 315C, 318C, 319C, 320C, 321C, 322C, 325C, 330C and M325C Excavators and 325C MHPU and 330C MHPU Mobile Hydraulic Power Units Engine and Pump Control – V2 – Controller – Replace

Prior to replacement of the controller, ensure that replacement is absolutely necessary. The controller is not normally the cause of a diagnostic code. Always check that power is available to the controller and the monitor. Battery voltage is required at contact 1 of connector 1. Ground is required at contact 2 of the harness connector for the controller.

When the controller is replaced, adjustments or calibrations are required. Refer to Testing and Adjusting, “Proportional Reducing Valve – Calibrate” and Testing and Adjusting, “Governor Actuator – Calibrate”.

  1. Turn the disconnect switch and the keyswitch to the OFF position.
  1. Disconnect the machine harnesses from the controller.
  1. Remove the controller.
  1. Verify that the replacement for the controller has the correct part number.
  1. Install the new controller.
  1. Connect the machine harness to the controller.
  1. Turn the disconnect switch and the keyswitch to the ON position.
  1. Verify proper operation of the controller.
  1. Calibrate the electronic governor. Refer to Testing and Adjusting, “Governor Actuator- Calibrate”.
  1. Calibrate the proportional reducing valve. Refer to Testing and Adjusting, “Proportional Reducing Valve – Calibrate”.