What are coding and feature activation on VAG cars?

Cars from the Volkswagen Group (VAG: Volkswagen, Seat, Skoda and Audi) contain dozens of control units. Each control unit has a coding: a set of parameters that determines which features are active and how they behave. The same hardware is used across many trim levels; the coding makes the difference.

Coding means changing those parameters with diagnostic equipment. Feature activation is a specific form of coding: a feature that is already present in hardware and software, but was disabled at the factory, is switched on. Nothing is fitted or replaced.

The best-known example is Apple CarPlay and Android Auto on the original infotainment screen. Many VAG cars with an MIB2 or MIB2.5 system already have the necessary hardware on board, but the feature has been locked at the factory behind a software licence.

The result of an activation is identical to a factory option. CarPlay appears as a menu item as soon as an iPhone is connected via USB. The original screen, the steering wheel controls and all other functions are retained.

Coding is done through the OBD-II diagnostic port, which on VAG cars is located under the steering wheel on the driver's side. A diagnostic interface connects the car to coding software on a laptop or phone. Commonly used tools are VCDS and OBDeleven.

For CarPlay, the actual work takes 15 to 30 minutes per car on average. The preparation, such as identifying the platform and software version, determines whether it works first time.

When activating CarPlay on MIB2 and MIB2.5, the work broadly follows these steps:

• Ignition on, engine off, and connect to the car.
• Back up the existing coding.
• Open the control unit for information electronics (address 5F).
• Change the coding for Apple CarPlay and Android Auto; on some units, adaptation channels as well.
• Switch the ignition off, wait briefly and restart the system.
• Test with a phone over USB and check that the coding has been saved.

Not every disabled feature can be activated through coding alone. For some features, the Volkswagen Group uses software licences tied to the individual vehicle. That system is called SWaP, ‘Software as a Product’. The dealer or manufacturer activates such a feature with a vehicle-specific activation code.

OBD coding changes the configuration of the control unit itself. On MIB2 and MIB2.5 this is the usual method for CarPlay and Android Auto. Other systems and features may require a licence or a different procedure.

Which route applies depends on the unit, the software version and sometimes the brand. Audis with MIB2, for example, sometimes use different adaptation channels from Volkswagen, Seat and Skoda, and some Audi units need extra steps related to component protection. The Virtual Cockpit in the Audi TT also requires a different approach.

A proper assessment beforehand prevents surprises. Record the make, model, year, infotainment system and software version before anything is changed.

MIB stands for Modularer Infotainment Baukasten, the Volkswagen Group's modular infotainment platform. MIB2 is found in cars on the MQB platform from around 2014 to 2017. MIB2.5 followed from around 2017, with a faster processor. Activation works roughly from model year 2015–2016; for earlier cars the software version is decisive. Both systems can be activated through OBD coding; the table at the end of this article lists the differences.

The distinction is not always clear-cut. Cars from 2016 and 2017 can have either system, depending on production date and option pack. Older MIB2 cars, roughly up to and including 2016, also often have an MDI connector instead of a standard USB port. In that case an upgrade to USB is needed before CarPlay will work.

Not every system is suitable for activation:

• Older systems such as the RNS 510/RCD 510, MIB1 (early Golf 7 generation) and the RNS 310 and RNS 315 have no CarPlay hardware.
• Composition Colour without a touchscreen is unsuitable, because CarPlay requires touch input.
• Older Audi MMI 3G and 3G+ is a different platform, not MIB2.
• MIB3, found in the Golf 8, Seat Leon 4, Skoda Octavia 4 and Audi A3 8Y among others, cannot be activated with standard OBD coding; CarPlay is often active as standard on these cars.

Whether activation will work depends on the infotainment system's software version. As a guideline, MIB2 versions 0245 to 0850 and MIB2.5 versions 0500 to 0915 are generally compatible. Higher versions should be checked in advance. Very old MIB2 firmware, version 0339 and below, sometimes lacks CarPlay functionality altogether; a firmware update at the dealer is then the first step.

A version number above 1000 usually indicates an MIB3 system. If in doubt, take a photo of the version information screen and note the vehicle identification number (VIN). With that, the infotainment system in the car can be looked up.

You can read the software version on the screen without any tools:

• Volkswagen, Seat and Skoda: MENU > Settings > System information (or Version information), and note the number after ‘SW:’.
• Audi: MENU > System settings > Version information, and note the SW number.
• Audi TT with Virtual Cockpit: use the MENU button on the steering wheel and go to Vehicle > System settings > Version information.

Coding software and interfaces are available to anyone, and ready-made instructions can be found online. Even so, things regularly go wrong. A wrong setting or adaptation channel can disable features or cause fault messages that are hard to trace.

In addition, for any coding, professional or not, a software update at the dealer can reset the setting to its factory value. This happens mainly during services that include a firmware update, recalls and technical service bulletins (TSBs).

The most common problems with amateur work are:

• No backup of the original coding, so it can no longer be restored.
• Coding a software version that does not support the change.
• Changes that are not saved, or a CarPlay menu that does not appear after a restart.
• On Audi: issues with component protection or different adaptation channels.
• A connection that drops while the coding is being written.
• Not checking the connector, so CarPlay fails because of an MDI port without a USB upgrade.

Many garages, dealers and body shops outsource coding. Each platform has its own coding schemes, software versions and exceptions, and keeping up with that knowledge takes time. The tools, such as VCDS, OBDeleven or VCP, also require licences and experience.

Outsourcing makes most sense for customer requests that do not come up every day, such as CarPlay on an older VAG model. The work then goes to a specialist who does it more often, and your own workshop stays free for regular servicing.

Carro Automotive activates Apple CarPlay and Android Auto on Volkswagen, Seat and Skoda with MIB2 or MIB2.5 and on the Audi A1, A3, Q2, Q3 and TT, at its workshop at Stavorenweg 4 in Gouda. The software version is checked beforehand. Consumer prices start at €120 (Volkswagen, Seat, Skoda) and €150 (Audi); volume pricing for garages and dealers is available on request.

If activation is not possible, there are two alternatives: a CarPlay module behind the original screen, from €249, or a new screen, from €199. The activation comes with a 2-year warranty.