This manual contains information concerning the operation and function of the Electronic vehicle management and control (V-MAC) IV Vehicle Management and Control with Co-Pilot Display. The information in this manual applies to vehicles built May 2011 and later. Please keep this manual in the vehicle at all times.
Note: Illustrations in this manual are used for reference only and may differ slightly from the actual vehicle. However, key components addressed in this document are represented as accurately as possible.
Service Procedures and Tool Usage
Anyone using a service procedure or tool not recommended in this manual must first satisfy himself thoroughly that neither his safety nor vehicle safety will be jeopardized by the service method he selects. Individuals deviating in any manner from the instructions provided assume all risks of consequential personal injury or damage to equipment involved.
Also note that particular service procedures may require the use of a special tool(s) designed for a specific purpose. These special tools must be used in the manner described, whenever specified in the instructions.
Every possible occurrence that may involve a potential hazard cannot be anticipated. Accidents can be avoided by recognizing potentially hazardous situations and taking necessary precautions. Performing service procedures correctly is critical to technician safety and safe, reliable vehicle operation.
The following list of general shop safety practices can help technicians avoid potentially hazardous situations and reduce the risk of personal injury. DO NOT perform any services, maintenance procedures or lubrications until this manual has been read and understood.
System Summary
The vehicle management and control (V-MAC) IV System is an electronic engine control system consisting of the following major components:
- Engine Control Module (ECM)
- Gauge Driver Module GDM (MRU and LEU models only)
- Instrument Cluster
- Vehicle Electronic Control Unit (VECU)
To enable vehicle management and control (V-MAC) IV to perform its engine management and control functions, the following sensors provide information to the system.
- Air Brake Application Sensor
- Air Suspension Sensor
- Air- Humidity Sensor
- Ambient Air Temperature (AAT) Sensor
- Intake Manifold Pressure (IMP) Sensor
- Intake Manifold Air Temperature Sensor
- Camshaft Position (CMP) Sensor
- Engine Coolant Level (ECL) Sensor
- Engine Coolant Temperature (ECT) Sensor
- Crankshaft Position (CKP) Sensor
- EGR Temperature Aftercooler Sensor
- Crankcase Pressure (CCP) Sensor
- Engine Exhaust Gas Recirculation (EGR) Differential Pressure Sensor
- Front Drive Axle Temperature Sensor
- Fuel Pressure Sensor
To enable vehicle management and control (V-MAC) IV to perform its engine management and control functions, the following sensors provide information to the system.
- Interior Cab Temperature Sensor (Optional)
- Engine Oil Level (EOL) Sensor
- Engine Oil Temperature (EOT) Sensor
- Engine Oil Pressure (EOP)
- Primary and Secondary Air Pressure Sensor
- Rear Drive Axle Temperature Sensor
- Accelerator Pedal Position (APP) Sensor
- Transmission Oil Temperature Sensor
- Engine Turbocharger Speed Sensor
- Vehicle Speed (Road Speed) Sensor
- Water in Fuel Filter Sensor
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)
- Fan Clutch Override Switch (Optional)
- Idle Shutdown Override 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.
Vehicle Electronic Control Unit (VECU)
The Vehicle Electronic Control Unit (VECU) is mounted underneath panel D as shown in . (CHU/CXU/GU model shown.) The Vehicle Electronic Control Unit (VECU) is an electronic control module which provides a wide variety of functions including:
- Cruise Control
- Diagnostic Trouble Code (DTC) Logging
- Differential Locking
- Idle Shutdown
- Maintenance Information
- Road Speed Limiting
- Speed Control
- Theft Deterrence