CAN-Bus adapter for car radio
Modern cars are not just mechanical devices, but complex computerized systems. For all components to work efficiently, a reliable communication system between the various electronic control units of the car is required. CAN-Bus solves this problem.

CAN-Bus (Controller Area Network) is an industrial networking standard originally developed for the automotive industry by Bosch in the 1980s. CAN-Bus allows microcontrollers and devices to communicate with each other without a host computer inside the vehicle.
The main advantages of CAN-Bus:
- High noise immunity
- Ability to work in real time
- Reliability of data transmission
- Reducing the complexity of vehicle wiring
Today, CAN-Bus is used not only in automobiles, but also in industrial automation, medical equipment and other areas.
CAN-Bus adapter: definition and purpose
CAN-Bus adapter is a device that allows you to connect to the car’s CAN bus and read/send data. Such an adapter serves as a bridge between the car’s CAN bus and an external device (for example, a car radio).
Main functions of the CAN-Bus adapter:
- Troubleshooting
- Reading data from sensors in real time
- ECU reprogramming
- Integration of additional equipment (actually, this function is the determining factor when working with a new car radio)
Why is a CAN-Bus adapter necessary: It allows access to information that is not available through the standard OBD-II diagnostic connector and provides the ability to interact more deeply with the vehicle’s electronic systems.
How does a CAN-Bus adapter help integrate a new car radio into a vehicle?
Once again, CAN-bus (Controller Area Network) is a network protocol used in cars to communicate between different electronic control units (ECUs). The car radio, like many other systems in a modern car, is often connected to the CAN-bus.
The CAN-Bus interface in the context of installing a car radio performs the following important functions:
1. It acts as a bridge between the radio and the car’s CAN bus:
- Many modern car radios do not have a direct connection to the CAN bus. The adapter converts signals from the CAN bus into a format understandable to the radio, and vice versa.
2. Maintaining the functionality of the steering wheel buttons:
- The adapter decodes signals from the steering wheel control buttons connected to the CAN bus and transmits them to the radio. This allows you to maintain the convenience of controlling the radio from the steering wheel.
3. Transferring information from the CAN bus to the radio:
- The adapter can read information from the CAN bus, such as vehicle speed, engine speed, door opening, etc., and transmit it to the radio display.
4. Support of standard car functions:
- In some cars, information about climate control, parking sensors and other systems is displayed on the display of the standard radio. The CAN-Bus adapter allows you to keep this information displayed even after replacing the radio.
In summary, CAN-Bus adapter:
- Ensures correct integration of the new car radio into the vehicle’s electronic system.
- Allows you to maintain the functionality of the buttons on the steering wheel.
- Allows you to display information from the CAN bus on the radio display.
Without a CAN-Bus adapter, installing a new radio can be difficult or impossible without losing some of the car’s functions. We have a useful article about setting up a CAN-Bus adapter for Teyes car radios.
CAN-Bus adapter for car radio – what does it look like?
On cars that have a CAN bus, it is most often used in the radio. The radio “learns” from the CAN bus such information as the state of the ignition key, whether the instrument panel backlight is on, and also from the bus you can take such information as the state of the handbrake (whether the car is on the “handbrake” or not), the speed of the car, for multimedia systems – whether reverse gear is engaged. Since all these signals are contained in the CAN bus, there is no separate wire for each of the signals in the radio connector, but only power and CAN bus wires. For example:
“+UB” is +12V constant plus
“CAN-FZG -” – can-bus (-)
“CAN-FZG +” – can-bus (+)
there is no wire from the ignition switch, no backlight.
To understand what a CAN-Bus adapter looks like, we recommend watching our video posted on our YouTube channel about an adapter for connecting a new radio to Volvo cars:
CAN-Bus adapter for car radio – how to choose?
Look at one of the CAN-Bus adapters – you can see that on one side the adapter has a universal ISO connector, and on the other side – specific connectors that are designed for connection to the standard wiring of a specific make and model of car.

Each connector has an exact match to the connector shape in the car. Plug-and-play connection allows you to connect the radio securely and without interfering with the factory wiring. For example, a CAN-Bus adapter for a Mercedes car radio will have connectors that are exactly the same in size and pinout as in the car itself. In order to choose the right CAN-Bus adapter, we recommend that you look at the information on the websites of adapter manufacturers (Carav or Connects2), and you can also fill out the form below so that we can contact you and choose the best option: