8 V-MAC Co-Pilot Operator's Manual The following switches and functions are also monitored to provide information related to driver actions. A/C Pressure Switch (Optional) Clutch Pedal Position (CPP) Switch Engine Brake Low and High Switch (Optional) Ignition key Power Takeoff (PTO) Switches (Optional) Service Brake and Parking Brake Switches Set/Resume Switch Speed Control On/Off Switch Starter Engaged Switch Input (Optional) Torque Limiting Switch (Optional) This manual provides a complete description of the system components, their functions and locations on the vehicle.