Vehicle ID ISO coding system paves the way for a smooth ride

Issue 28 – June 2011

The Vehicle Identification Number (VIN) coding system serves as a frame of reference for establishing the structure of identification numbers for manufactured vehicles. The VIN system is contained in ISO 3779:2009 Road vehicles – Vehicle identificationnumber (VIN) Content and structure and ISO 3780:2009 Road vehicles – World manufacturer identifier (WMI) code.

The VIN is a structured combination of characters (17 in total) assigned to each vehicle by the manufacturer. Its aim is to ensure the unequivocal identification of any vehicle for a period of 30 years, without requiring any other information. The VIN consists of three sections which are clearly specified in ISO 3779: the World Manufacturer Identifier (WMI), the Vehicle Descriptor Section (VDS) and the Vehicle Indicator Section (VIS).

Most VINs are displayed on the nearside (passenger side) of the windscreen. A VIN can be seen from outside the vehicle, and under the bonnet (on the engine, for example). VINs are an excellent way to combat vehicle 'cloning', a scam that has grown at an alarming rate over the last few years. Cloning is a term used to describe a vehicle that has had its identity changed, usually because it is stolen.

Manufacturers' marks

The WMI refers to an identification code given to vehicle manufacturer. ISO 3779 defines the manufacturer as a person, firm, or corporation that issues the certificate of conformity or that demonstrates compliance and assumes product liability for a vehicle ready for operation, independently of the location of the assembly plant. The manufacturer is responsible for the uniqueness of the VIN.

The WMI consists of three characters (capital Roman letters or Arabic numerals). It is assigned by the relevant authority of the country in which the manufacturer has its headquarters in agreement with SAE International (Society of Automotive Engineers) in the USA. The first character designates a geographic area, the second character designates a country within a specific geographic area, and the third character designates a specific manufacturer.

Detailed description

The second section of the VIN known as VDS consists of six characters (alphabetical or numerical) aiming to provide information describing the general attributes of the vehicle. The coding and sequence of this section are determined by the manufacturer. If the manufacturer does not use one or more of these character spaces, the unused spaces shall be filled by alphabetical or numerical characters of the manufacturer's choice.

Proper ID

The third section of the VIN, the VIS, consists of eight characters, the last four being necessarily numerical. When used in combination with the other two sections, WMI and VDS, the VIS ensures the unequivocal identification of a given vehicle. Any unused position must be filled by a zero in order to obtain the total number of required characters. The first two characters of this section may designate the model year of the vehicle or the calendar year in which it was produced as well as the manufacturing plant.

In some countries, car manufacturers are not allowed to assign a model year (MY + 1) for a vehicle before a specific date that has been determined by the local authorities of the relevant country. This is the case, for instance, in Argentina, where a MY + 1 cannot be declared before the month of April of each year, and in Turkey, where the authorities have determined the month of August of every year as the mandatory date for declaring an MY change.

ISO 3779 and ISO 3780 both clearly specify the authorised characters. Only Arabic numerals and capital Roman letters can be used, except for the letters I, O and Q. Also, ISO 3779 specifies the Arabic numeral or the chronological Roman letter to be used for each year (1 for 2001 – 9 for 2009, A for 2010 – L for 2020, – Y for 2030).

The VIN display, the VIN printed on documents is shown on one line. The VIN as displayed on the vehicle or a manufacturer's plate is represented on either one or two lines, without blanks and with no section being split. In the Maghreb countries (Algeria, Morocco, and Tunisia), regulations require that specific symbols of each manufacturer should be shown on both sides of the 17-character-VIN.

Relationship with legislation

Throughout the world, both the VIN and WMI codes are regularly referenced and referred to in the legislation of every country for the type-approval of vehicles before being marketed. Yet, Venezuela refers to ISO 3779 but also requires a check digit and a production plant code for the 9th and 10th characters of the VIN.

The check digit for the 9th character is calculated using a formula which is provided for in Venezuelan legislation and derived from an American Standard on the VIN. For such calculation, each VIN character has a value of 0 through 9. The 10th character designates the production plant and is at the manufacturer's discretion. However, two production plants cannot be assigned with the same code (letter or figure). This type of 17-character VIN structure is also required in the Persian Gulf countries, China, and Mexico.

Brazil, the Gulf countries, and Russia do not refer to ISO 3779 for vehicle identification, but to national regulations that are strictly based on ISO 3779, in terms of both form and content.

In summary, both ISO 3779 and ISO 3780 establish, on a world-wide basis, a coding system to identify both the vehicle and the vehicle manufacturer. The 17-character VIN is the vehicle 'ID', from the date of manufacture to the date of destruction. It is used for technical services (spare parts and after-sale services) but also for administrative (certificate of registration, roadworthiness test, and insurance) and legal purposes (thefts, accidents, and litigation). PSA Peugeot Citroen extensively uses these two clear and accurate Standards, in Europe and all over the world.

This article is written by Dominique Bouvere. Bouvere has worked with PSA Peugeot Citroën for 35 years and is the international department coordinator responsible for regulatory and standardisation issues. This article is summarised with permission from ISO Focus+, April 2011.

(Note: See the New Zealand Transport Authority website for more information on VINs in New Zealand.)

Related Standards

  • ISO 3779:2009 Road vehicles – Vehicle identification number (VIN) – Content and structure
  • ISO 3780:2009 Road vehicles – World manufacturer identifier (WMI) code

Published in transport.