Bus and Truck
Modern buses and trucks incorporate electronic modules, microcontrollers, devices, actuators and sensors to facilitate their efficient control and operation. These systems work together to achieve pollution control, fuel efficiency, performance, safety, navigation, vehicle diagnostics, maintenance monitoring and other vehicle related requirements. Important electronic modules in these vehicles include the Engine Control Unit (ECU), Transmission Control Unit (TCU), Anti-lock Braking System (ABS), Traction Control Unit (TCU), Power Steering Control Unit, Airbag Control Unit and Body Control Modules (BCM). The modules get their inputs from sensors attached to various mechanical components to measure speed, temperature, pressure etc. To communicate with each other, a dedicated internal communication network called the Vehicle Bus connects different modules and other components. The Vehicle Bus uses specialized protocols like CAN bus to achieve critical vehicle communication characteristics such as assurance of message delivery, non-conflicting messages, speedy message delivery, EMF noise resilience and redundant routing.
The SAE J1939 standard is the recommended practice for Vehicle Bus standardization and is widely used by diesel engine manufacturers for heavy duty vehicles including off-highway, buses and trucks. Another relevant standard is SAE J1708, a standard means of data transfer for heavy duty vehicles. The SAE J1587 standard is used in trucks and buses to promote consistency between software in different electronic control units and together with SAE J1708, the aim is to lower the cost and complexity of developing and maintaining microcontroller devices in trucks and buses.
CAN based Electronic Logging Devices (ELD) are used to record driver performance data from the ECU via CAN bus. ELDs supply data at specific time intervals and according to designated event and status changes. The data relates to fuel consumption, torque, cruise control, high speed and braking events, engine run and idling time etc. and is used to provide performance feedback to drivers with the goal of improving efficiency. The data loggers are attached to the vehicle bus using a standard J1939 connector, though occasionally a connection to a J1587 network is needed for simultaneous data gathering.
Kvaser offers CAN bus connectors and dataloggers that are fully compatible with the J1939 vehicle bus standard. The Kvaser Linx J1587 adapter is a single channel add-on cable that provides access to a J1587 bus network. It logs both CAN and J1587 data simultaneously. It interconnects the CAN bus and either your existing datalogger or any Kvaser datalogger in series. Dual-channel Kvaser CAN bus interfaces and standalone dataloggers that can be connected with Kvaser Linx J1587 include the Kvaser Memorator Professional HS/HS and Kvaser Memorator Pro 2xHS v2, which comes with advanced features such as message filtering, triggers, error detection and generation, and silent mode. These are fully compatible with the J1939 vehicle bus standard.
The Kvaser Leaf Light HS v2 J1939-13 Type II CAN connector can be used to connect a vehicle microcontroller to a PC or output device in a J1939 compliant bus or truck. Meanwhile, the dual channel Kvaser USBcan R v2 and single channel Kvaser Leaf Light R v2 both support high speed CAN and are fully compatible with the J1939 vehicle bus standard.