Software-defined vehicle

A software-defined vehicle is a car, scooter or truck whose features are decided mainly by its software, so it can gain new features and fixes for years after it leaves the factory. In an older vehicle, a feature such as the braking behaviour was fixed in the hardware when it was made. In a software-defined vehicle, the maker can change it by sending an update.

Here is how it works in general. The vehicle has a few powerful computers instead of dozens of small ones, connected to sensors and to the parts they control. The software is built in layers, so that a new feature can be added without redoing the hardware. The vehicle is connected to the maker's cloud. The maker writes an update, tests it, and sends it over the air to every vehicle, much like a phone update. The vehicle installs it, often overnight.

Some makers sell features by subscription, so the owner pays for a feature that is already in the vehicle and is switched on by software. There are risks. An update can contain a fault, so the maker must test it, update in stages, and be able to go back to the older version. The vehicle can be attacked through its connection, so updates must be signed by the maker and checked by the vehicle. A United Nations (UN) regulation, R156, requires makers to manage and record software updates. India has a matching Automotive Industry Standard, AIS-190. In June 2026, the road transport ministry published a draft rule to make it mandatory.

Take, for example, an electric scooter whose maker sends an update that improves the range by a few kilometres by changing how the motor uses the battery. Consider a car whose maker adds a new driver-assistance feature a year after purchase, and charges a subscription for it. Imagine a recall for a software fault. It is fixed with an update, so the owner does not have to visit a workshop.

Pages that describe the parts are vehicle over-the-air platforms, vehicle electrical architecture, the vehicle operating system and the connected-vehicle cloud. The small computers it replaces are described under electronic control units. Because the vehicle changes after sale, each update must still pass safety certification, and the model connects to aftermarket services, since the maker keeps earning from software.

How is it different from a connected vehicle? A connected vehicle only sends data to a cloud. A software-defined vehicle also receives software that changes how it behaves.