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Vehicle software

What Is an OTA Update?

An over-the-air update, often shortened to OTA update, is a vehicle software update delivered remotely through a cellular or Wi-Fi connection instead of a normal workshop visit.

Last reviewed: October 1, 2026CarGlossary Phase 2 P1 glossary
Simple definition

An OTA update lets an automaker send new software, fixes or calibrations to a connected vehicle after it has left the factory.

What can an OTA update change?

OTA updates can cover simple items such as infotainment software, maps, apps and user-interface fixes. In more advanced vehicles, they may also update driver-assistance calibration, battery and charging logic, energy management, body control functions or other electronic systems.

The exact scope depends on the vehicle architecture, legal approvals, cybersecurity process and how much of the car is designed to be updated safely.

How OTA updates work

The vehicle downloads an update package through its connected services link, then checks authenticity and compatibility before installation. Modern update systems usually use signed software, version tracking and a controlled installation process.

For safety-critical systems, the update process may include dependency checks, fallback software, rollback logic or instructions to keep the vehicle parked while installation completes.

Why OTA matters for software-defined vehicles

OTA capability is a core part of the software-defined vehicle idea. If more vehicle functions are controlled by software, automakers need a disciplined way to fix, improve and secure that software over time.

OTA also connects with E/E architecture, zonal architecture and vehicle domain controllers, because the vehicle's electronics must support reliable update delivery.

Limits and misconceptions

An OTA update does not guarantee a car will keep gaining major new features forever. Updates depend on hardware capability, software support, network coverage, regulatory approvals and the automaker's update policy.

OTA can also create confusion when a recall is repaired by software. The fix may arrive remotely, but it is still a safety action if the automaker or regulator treats it as one.

What to compare as a buyer

  • Does the manufacturer publish release notes?
  • Are updates free, subscription-based or feature-dependent?
  • Can safety and powertrain software be updated, or only infotainment?
  • Is there a rollback or recovery process if installation fails?
  • How long does the automaker promise software support?
Software-Defined VehicleE/E architectureZonal architectureVehicle domain controllerAI-Defined VehicleDriver monitoring system

Sources

CarGlossary note:

Feature names, connector support, diagnostic behavior and EV specifications can vary by model year, trim, software version and market. Always verify the exact vehicle documentation before buying, repairing or relying on a feature.