299D and 299D XHP Compact Track Loaders and 272D and 272D XHP Skid Steer Loaders Machine Electronic Control System Caterpillar

The machine ECM gathers information from the switches and sensors. The information is processed by the software. The ECM will then activate the indicators, gauges, solenoids, and actuator.

The machine ECM will communicate with the Caterpillar Electronic Technician (ET) over the Cat Data Link.

The machine ECM utilizes the following components for the input signals:

• Left Joystick

• Right Joystick

• Auxiliary Inputs

• Service Tool Connector

• Switch (Arm Bar)

• Switch (Auxiliary Electrical Control)

• Switch (Work Tool Level Control)

• Switch (A/C Control)

• Switch (HVAC Fan Speed Control)

• Switch (Temperature Control)

• Switch (Door)

• Switch (Key Start)

• Switch (Parking Brake)

• Switch (Seat)

• Switch (Engine Oil Pressure)

• Switch (Joystick Patter Changer)

• Switch (Hydraulic Lockout and Interlock Override)

• Switch (Left Hand Trigger Multifunction)

• Switch (Creep Control)

• Switch (Ride Control)

• Switch (Air Filter Restriction)

• Switch (Hydraulic Filter Bypass)

• Switch (Lift Arm Raise/Lower)

• Sensor (Cylinder Head End Pressure)

• Sensor (Bucket Inclinometer)

• Sensor (Engine Speed Control Pedal)

• Sensor (Left Motor Speed)

• Sensor (Right Motor Speed)

• Sensor (Engine Speed Control Knob)

• Sensor (Hydraulic Oil Temp)

• Sensor (Coolant Temperature - Radiator)

• Sensor (Fuel Level)

• Engine ECM

The machine ECM controls the following components:

• Solenoid Valve (High Flow)

• Solenoid Valve (Aux A1)

• Solenoid Valve (Aux A2)

• Solenoid Valve (Demand Fan)

• Solenoid Valve (Travel Pilot ON/OFF)

• Solenoid Valve (Implement Pilot ON/OFF)

• Solenoid Valve (Lift Arm Raise)

• Solenoid Valve (Lift Arm Lower)

• Solenoid Valve (Right Pump Forward)

• Solenoid Valve (Right Pump Reverse)

• Solenoid Valve (Left Pump Forward)

• Solenoid Valve (Left Pump Reverse)

• Solenoid Valve (Work Tool Dump)

• Solenoid Valve (Work Tool Rackback)

Illustration 1	g02907837

Location of Machine ECM

Illustration 2	g02773197

Location of Cat ET Service Connector

Illustration 3	g02773199