GPS tracker with CAN bus data reading

What can it tell me? How can I access this data with a GPS tracker? These are common questions when buying a GPS tracker.

First, let's explain what the CAN bus actually is. The CAN bus (Controller Area Network) is an important communication bus in modern vehicles that connects the various electronic systems and units in your vehicle and lets them communicate with one another.

Reading data from the CAN bus is an important tool for vehicle diagnostics and monitoring. There are various ways to access the data on the CAN bus, including reading via OBD (On-Board Diagnostics) or connecting cables directly to the bus.

The data tells you the fuel level in the tank and how it changes. You can also see the fuel consumption for a given trip or the average consumption. This lets you monitor and evaluate your drivers' driving style. The odometer reading is carried over too, so the kilometres driven recorded in the trip journal match the vehicle's actual reading. Our system can download all this data automatically and save it against individual trips as the trip journal is created. That way you have everything to hand and can check at any time how your car has been treated.

Ways to connect

OBD – reading data via a standardised connector

One of the most widely used ways of reading data from the CAN bus is via the OBD connector. OBD is a standardised diagnostic connector found in every modern vehicle. It provides access to diagnostic information and the data on the CAN bus using the OBD-II communication protocol. By connecting the GPS tracker through this connector, you get not only the vehicle's position but also other diagnostic data. In the SensFleet application you can therefore see the fuel or battery level, as well as the driver's driving style.

Where to find the OBD connector

You can usually find the OBD connector near the instrument panel or under the dashboard of the vehicle. Here are some typical places where the OBD connector is often located:

Under the instrument panel: One of the most common locations for the OBD connector is under the instrument panel on the driver's side. When you sit behind the wheel, look under the dashboard towards your feet and try to find an open space or a cover marked “OBD” or “Diagnostics”.

Under the bonnet: In some cases, the OBD connector may be located in the engine compartment. If you can't find the connector inside the vehicle, check under the bonnet and look for a cover or socket marked “OBD”.

It is important to note, however, that the location of the OBD connector can vary depending on the specific model and manufacturer of the vehicle. The data transmitted can also differ by vehicle type, and not every vehicle sends all the data. If you have trouble finding the OBD connector in your vehicle, we recommend checking the vehicle's owner's manual. If you're not sure whether we can read data from your vehicle, or you don't have the manual, you can also contact our technical support team, who will be happy to help.

Connecting cables directly to the CAN bus

Another option is to connect cables directly to the CAN bus, the physical bus that links the various electronic units in the car. Connecting cables directly to the CAN bus requires advanced technical knowledge and special diagnostic tools. This method gives access to more extensive data and more detailed information about how the vehicle's individual systems are working. It is important to remember, however, that unauthorised access or incorrect handling can damage the vehicle, which is why this work is best left to professionals. Our technicians can connect to the wiring by cutting into the individual cables. For new or leased cars, we recommend using the contactless eCAN reader, which clips onto the cables without damaging them, so the vehicle's warranty is not affected.

Another advantage of connecting directly to the cables is that everything, including the GPS tracker, is hidden under the vehicle's dashboard. This prevents unwanted or improper handling by your employees, as well as any undesirable disconnection.