





Table of contents
A vehicle data device is any device that captures, accesses or processes data from a vehicle. Telematics devices are a type of vehicle data device that collect operational and diagnostic data to give fleet managers greater visibility into vehicle location, performance, maintenance needs and driver behaviour.
What is a vehicle data device (VDD)?
Vehicle data devices can be either connected or non-connected. Connected devices collect vehicle data and transmit it remotely to a platform where it can be analysed and turned into actionable insights. Non-connected devices store the data for later retrieval and analysis.
The most common vehicle data devices in fleet management are telematics devices. These collect vehicle operation, location and condition data, enabling fleet managers to monitor vehicle performance, optimise utilisation, schedule maintenance and improve driver safety.
How does a vehicle data device work?
- First, you need to connect the VDD to the vehicle, either through the OBD-II port, CAN bus or an embedded vehicle system. (Connection methods vary by vehicle make and model.)
- The device will read and process vehicle data, such as engine status, mileage, fuel consumption and fault codes, before storing it locally.
- If the VDD is a connected device, it can transmit the data to a cloud platform using cellular, satellite or Wi-Fi networks where it is analysed and presented as reports, alerts, dashboards or other human-friendly displays.
- Fleet managers, maintenance technicians, drivers and other team members can read these insights in real time — to monitor factors like location or maintenance needs — or investigate a past time period to evaluate performance, utilisation and driver behaviour.
Connecting to the vehicle's systems
Whatever the connection method, the VDDs have the same purpose: to access the vehicle's electronic systems and retrieve data from its onboard sensors and control units.
How different connection methods work:
- OBD-II port: the VDD can be plugged directly into the port.
- CAN bus: the device must be hardwired into the vehicle’s CAN bus network.
- Embedded vehicle system: the VDD is built into the vehicle by the manufacturer and accesses data directly from the vehicle’s systems.
Transmitting data to fleet management software
Vehicle data is sent to the telematics platform securely via cellular, Wi-Fi or satellite networks. The fleet management system organises the data into dashboards, notifications and reports so it is easy to interpret visually. This supports operational analysis and decision-making.
Some vehicles provide more limited data than others, depending on factors such as the manufacturer, model, year and the level of access available through the vehicle's electronic systems. Use our Vehicle Compatibility Checker online tool to find out which Webfleet solutions are the best fit for your vehicles in order to visualise the data that’s most important to you.
What vehicle data can you access?
VDDs are designed to give fleet managers greater visibility over their operations so they can understand exactly what is happening and where inefficiencies could be removed. These inefficiencies could be caused by driver behaviour, vehicle utilisation or route planning, among other operational factors.
Bear in mind that the data available can differ depending on vehicle specifications and manufacturer support.
Vehicle location and mileage
VDDs typically contain GPS receivers to record vehicle location and read mileage from the vehicle’s own electronic systems. Knowing where a vehicle is, the route it travelled and how far it was driven is crucial for fleet managers to improve scheduling, optimise utilisation and respond quickly to issues in the field.
Fuel consumption data
Since fuel is one of a fleet business’ greatest expenses, monitoring fuel consumption across different routes is key for identifying and eliminating unnecessary spikes that could needlessly raise your operating costs.
Engine and diagnostic information
VDDs access engine performance data and diagnostic trouble codes (DTCs) from a vehicle’s electronic system so they can flag up anomalies or warnings related to potential issues. Fleet managers can then take action to stop these issues from developing, avoiding costly repairs later on.
Driver behaviour data
Driving behaviour information can be pulled from a vehicle’s electronic system or may be collected by the sensors on the VDD itself. Proof of speeding, harsh braking, sudden acceleration or idling — and their impact on vehicle conditions and fuel consumption — is critical material for training drivers in safer, more efficient driving practices.
Why are vehicle data devices important for fleet management
VDDs eliminate guesswork for fleet operators. They reveal reliable, real-time information that helps fleet managers make better decisions to optimise operations.
Improving fleet visibility
Knowing where your vehicles are at any moment is essential for monitoring whether jobs are on schedule and intervening to support drivers if an incident occurs. By collecting historical data, fleet managers can regularly benchmark performance — e.g. vehicle utilisation, fuel consumption and downtime — to ensure the business is on track for reaching its predefined strategic objectives.
Supporting vehicle maintenance
VDDs access vehicle health and diagnostic data directly, giving maintenance technicians the exact information they need to target emerging issues and repair components before they cause more serious problems. This preventative maintenance approach helps fleets reduce downtime, cut repairs costs and extend vehicle lifespan.
Enhancing operational efficiency
Vehicle data tells the story of what's happening across your fleet in numerical form. It makes it easier to identify inefficiencies, such as route backtracking, large gaps between jobs or vehicles spending excessive time idling. By understanding where and when these issues occur, fleet managers can optimise routes, improve resource allocation, reduce fuel consumption and increase overall productivity.
Where is a vehicle data device installed?
A VDD is designed to access the vehicle's electronic systems and retrieve data from its onboard sensors and control units. Some VDDs plug directly into the vehicle's OBD-II port, providing a quick and straightforward connection. Others are hardwired into the CAN bus network, allowing them to access a wider range of vehicle data. In newer connected vehicles, the VDD may already be embedded by the manufacturer, enabling it to collect data directly from the vehicle's systems without the need for additional hardware installation.
Is a vehicle data device the same as a GPS tracker?
No, a vehicle data device is not the same as a GPS tracker. GPS trackers fall under the broad category of vehicle data device: technology that collects, accesses or processes vehicle data (in this case, location data). This means that while a GPS tracker is a type of VDD, not all VDDs are GPS trackers.
What a GPS tracker does
GPS trackers are designed to collect data specifically about location, movement and routes. They are used in fleet management for checking drivers stick to planned routes and monitoring progress against ETAs communicated to customers.
What additional data does a vehicle data device provide?
Vehicle data devices provide a wide range of vehicle and driver data, including speed, fuel consumption, engine performance, fault codes, maintenance status, idling time, utilisation and driver behaviour metrics.
What are the benefits of using a vehicle data device?
The key benefit of using a VDD is the visibility gained. Fleet managers can view vehicle activity, performance and condition in real time, and make data-backed decisions rather than assumptions. By providing insights into vehicle location, utilisation, maintenance needs and operational efficiency, VDDs help fleets reduce costs, minimise downtime, improve productivity and keep vehicles running safely and reliably.





