One Example of a Software Architecture for a Configurable, Intelligent Vehicle Electrical Control System 2001-01-2741

The increasing complexity of the electrical and electronic systems on trucks requires a more sophisticated electrical control system. Replacing many of the discrete electronic controls and wiring with a central Electrical System Controller (ESC) allows for easier integration of system components and improved system response. The use of software control within the Electrical System Controller, provides opportunities for enhanced system capabilities and a fluid platform for future development.

This paper examines the software architecture employed within an Electrical System Controller and also examines the factors that govern the software's design. These include a requirement for the ESC to be highly configurable to accommodate a variety of features desired by customers.

The chosen hardware platform for the Electrical System Controller consists of an electronic assembly with a central processor that monitors multiple analog and digital inputs and data from SAE J1939(CAN) and SAE J1708 networks, to determine the state of the various systems on the truck. The system inputs are processed through software modules. The results of this software processing are high current outputs, relay driver outputs, and messages sent out on J1708 and J1939 networks. The ESC software allows for advanced diagnostics including the ability to detect faulty sensors, wiring faults, overcurrent conditions, and errors in data link transmission and reception. Fault conditions can be sent to the electronic gauge cluster for display and can also be made available for retrieval by diagnostic tools.