ZCS Structure

The Central Coding Key is 37 digits and is divided into 3 segments. The segments represent specific information about the vehicle.

Each segment ends with a "check digit". A check digit is a number or letter used by the coding software to detect unacceptable or implausible codes.

The segments of the ZCS are:

GM = Basic Features 

The 9 digits of the GM describes:

• Type of vehicle (E38, E46 etc.)
• Body style.
• Body equipment.
• Country version.
• Basic language.
  Fig 1: Identifying GM 9 Digit Coding

  Courtesy of BMW OF NORTH AMERICA, INC.

SA = Special Equipment 

The 17 digits of the SA describes:

• Vehicle equipment
  • Power windows.
  • Sunroof.
  • DWA.
  • FZV.
  • Xenon lights.
  • Headlight washers
  • DSC, etc.

VN = Version Number 

The 11 digits of the VN describes:

• All data relevant for coding which are not Basic Features or Special Equipment. (E.g model year dependent data, software and hardware versions, coding instructions, etc.)

Originally the ZCS code also contained a fourth line called AM = Drive Management.  This 11 digit code was supposed to contain information specific to powertrain control modules. The AM was never used and was deleted from the central coding label early on.