Skip to content

What is Canbus? How does it work and ESSENTIAL INFORMATION

  • Lexicon
  • 4 min read
Canbus connector JCB Kohler

Canbus connector JCB Kohler
Canbus connector JCB Kohler

What is canbus system?

CANBUS is a specialized vehicle communication system that allows the exchange of data and information between different systems and circuits. It allows communication between components and the vehicle’s main computer, as well as between the components themselves, which can control other parts and gather information from sensors. CANBUS is an abbreviation for Controlled Area Network Bus.

With this system, it is possible to systematize the operation of individual systems, helping to increase driving comfort and maximize the vehicle’s power. Modern car models use CANBUS for efficient communication between the engine, sensors and other important systems.

CAN bus is a standardized vehicle information system that allows communication between the various electronic control systems of a vehicle. Electronic control units (ECUs) are the vehicle’s component where information is stored. They also allow information to be recorded and transmitted from other vehicle components. The CAN bus is standard equipment in all vehicles, including cars, trucks, buses, ships, as well as electric vehicle batteries, machinery and more.

How does it work?

CAN bus systems in a vehicle play a role similar to the nervous system in the human body. Electronic control systems in a vehicle are like body parts, and the system is the connection between them. Various electronic control systems can collect information that needs to be transmitted to other elements in the network.

This network allows the vehicle’s electronic control systems such as the engine, antilock brake/ABS, airbags, cruise control, electronic fuel injection, automatic transmission and battery systems to communicate with each other despite the lack of a central computer. Its main task is therefore to prepare and transmit information, such as sensor data, within the CAN bus network.

This data is then accepted by all electronic control systems. Once the data is received, the electronic control systems decide whether to accept or ignore it.

What is can rail?

Communication between electronic control systems within the CAN network is carried out via CAN buses. There are four types of CAN rails:

  • Data rail – the only rail that is actually used to transmit data
  • Error rail – contains nodes for error detection
  • Overload rail – activates when there is a delay in data transmission between the data bus and the remote rail
  • Remote rail – a rail that calls up information from a specific identifier

Here is some key information on how CANBUS works:

1 Data Multiplexing: CANBUS works on the principle of multiplexing, or combining multiple signals into a single data stream. Each ECU (Electronic Control Unit) on the CAN network has its own unique identifier, which determines its function and priority. This makes it possible to transmit vehicle status information such as speed, engine rpm, temperatures, fuel level, etc. between different systems.

2 Wiring Reduction: One of the main goals of CANBUS was to replace the miles of cables found in a car with a single communication line that supports all systems.

3 Resistance to interference: CAN networks are characterized by high immunity to external electromagnetic interference, such as lightning or operation near the machine. Thanks to the use of so-called differential signals, error frames and checksums, errors in the form of skewed bits are extremely rare.

Pros coming from canbus system?

  • Low cost and simple operation
    Electronic control systems can communicate over a single CAN system, eliminating the need to install dedicated wiring and reducing vehicle weight, error risk and cost.
  • Centralization
    Provides centralization of diagnostics, configuration and data logging within a single entry point on the CAN network.
  • Robustness
    Electrical and electromagnetic interference does not affect system performance. The CAN bus standard is an ideal solution for safety-critical applications (such as driver safety).
  • Efficiency
    Data is prioritized, avoiding interference with other buses.