The CAN bus (Controller Area Network) is a vehicle’s internal communication network: the “nervous system” over which dozens of electronic control units (engine, brakes, transmission, climate…) exchange messages in real time, with no central computer.
How it works
Every control unit sends and reads messages on the same shared wire, each tagged with a priority. This makes available a far richer dataset than the OBD-II port alone exposes: real fuel use, fluid levels, temperatures, battery status, manufacturer-specific data. That’s why higher-end telematics integrates directly with the CAN bus.
CAN bus in fleets
Reading the CAN bus enables more accurate reports on fuel use, wear and driving behaviour. On connected vehicles this same data is often already available via OEM telematics with no work on the vehicle. Optivo captures it either way in its fleet tracking platform.
FAQ
What’s the difference between CAN bus and OBD-II?
The CAN bus is the internal network all the vehicle’s data travels on; OBD-II is a port that exposes part of it in a standard format for diagnostics. Advanced telematics reads the CAN bus for more complete data.
Does CAN bus access require hardware?
Traditionally yes, via a dedicated connection. On connected vehicles, however, much of that data arrives from the manufacturer over the cloud, with no installation.