Boxcodes, EPK, ASW and CAL

This article explains the identifiers used for VAG ECU software and calibration data.

What is a boxcode?

A boxcode is the VAG identifier for the ECU software used for a specific vehicle configuration.

A boxcode also has a version, for example:

Boxcode: 5G0906259Q

Version: 0003

Different boxcodes or boxcode versions may use different calibrations, even when the vehicles use the same ECU family.

The EPK identifies the ECU software platform and application software version.

Example:

EPK: SCGA05

This can be split into:

SCG | A05

SCG identifies the Simos 18.10 ECU platform.

A05 identifies the ASW version.

ASW means Application Software.

It contains the ECU program logic, such as torque calculation, boost control, fueling, ignition control and diagnostic functions.

CAL means Calibration.

The CAL block contains the maps, tables, axes and constants that are edited in the Tune Editor.

In simple terms:

ASW = Program logic

CAL = Maps and calibration data

Multiple boxcodes can use the same EPK and ASW version, while using different CAL blocks.

Therefore, the following does not guarantee compatibility:

• Same ECU family
• Same EPK
• Same ASW version

Important: The correct definition must match the exact CAL and boxcode version.