M312, M315, M318 and M320 Excavators Hydraulic System Caterpillar

The electronic control system controls the output from the engine and from the pumps through the controller. The operator selects the power level with the power mode switch on the right console. The controller establishes the correct power mode by electronically modulating the pilot signals that are directed to the pump controls. The controller sends the signal pressure to the pump so that the pump can provide optimum output.

The electronic control system has the following major functions:

• When a large load is placed on the machine, the system causes the pumps to destroke. This allows the maximum horsepower from the engine.

• The system controls the output of the pumps at the optimum power mode from different power mode settings. This allows the machine to operate at the optimum speed. This also reduces the fuel consumption.

• At a "No Load" condition, the system automatically decreases the engine speed for improved fuel consumption and for improved noise level.

Reference: For the "Electronic System" information, refer to the Service Manual for the machine that is being serviced.