What's in a VIN?

Decoding Vehicle Identification Numbers puts the brakes on auto theft, cloning and chop shop operations


     Federal regulations in Canada and the United States require the VIN to be affixed in such a way that removal or alteration is difficult. Each manufacturer uses a unique type of plate or embossing process to achieve this, and it is possible to determine the manufacturer just by the VIN plate style or sticker. For example, General Motors uses a plate, which includes a barcode and is attached with six-point rivets. Ford, on the other hand, utilizes an embossed plate with no barcode, while Honda employs round rivets and Toyota uses five-point rosettes, Smylie reports.

Double protection

     Vehicle manufacturers locate paper labels, known as safety certificates, on the inside edge of the driver's door. Smylie reports these labels contain similar information to that found in the VIN, but also may house a barcode, assembly date information, the gross vehicle weight, axle ratios, transmission information and key codes. In newer vehicles, Smylie notes this certificate may also describe anti-theft devices.

     Data found on the door label can be compared to — and should match — that found in the dash-mounted VIN. However, there may be several reasons why the VIN and safety label do not agree. The vehicle could: Be stolen or registered under a false VIN, have been badly damaged and the dash or door replaced, or have been written off and repaired by a "backyard mechanic" for resale.

     Under these circumstances it is wise to investigate further. VINs are stamped or affixed to most major vehicle parts, and comparisons should be made to several of these areas if a discrepancy is found.

Secret hiding places

     Other VIN locations, sometimes referred to as anti-theft labels, can be found in numerous places. For instance, VINs are stamped or affixed to the front fender and bumper, the hood, the left and right door, rear quarter panels, the trunk and the rear bumper. Sometimes VINs are imprinted on rear passenger doors as well. The codes are also stamped on the engine, transmission and drive train to discourage reassembly of wrecked or stolen vehicles. And some, but not all, vehicles will also have the serial number positioned in confidential locations, such as under the carpets; on the interior of the vehicle's "A" post, the support that runs from the top of the front door along the windshield, or "B" post, the support that runs midway through the vehicle; and on firewalls.

     The VINs in these locations may be whole or partial. In addition, vehicles with higher-end, anti-theft devices may not be required to stamp this data in all of the above locations.

     Data found in these areas are designed to prevent "chop shops" from taking wrecked or stolen vehicles and reconstructing them for sale.

     Damaged vehicles are often repaired with factory-issued parts, which bear what is called an R-dot, basically a sticker affixed to all factory parts that is nearly impossible to remove without obvious damage. 3M Company produces a sticker used by several major manufacturers that displays stripes on both the removed piece and the remaining portion when tampered with. Other stickers in use leave a residue that is visible under ultra-violet light. Manufacturers closely monitor the distribution of replacement parts through the use of such tracking methods, says Smylie.

     Airbags also display a serial number that in most new cars can be matched to the VIN. However, unless the vehicle has had the airbags deployed, examining them must be left to an expert. Airbags carry enough force to kill an adult and should not be accessed by anyone other than an expert in this field, Smylie advises.

A whole new VIN

     There are two ways to alter a VIN. The simple way is to obliterate the digits, which may be removed, chiseled, covered up or otherwise rendered unreadable. This technique is used to slow police down by making it harder for law enforcement officials to identify the vehicle or its owner. Eventually, using data found in other VIN locations, officials will learn whether the vehicle has been stolen or is wanted in a crime-related offense. It is just that without the dash-mounted VIN, it takes longer to process the vehicle and access hidden VIN locations.

     The most difficult changes to catch are the forgeries. Police officers typically are not trained to detect minor VIN changes. They run the VIN through whatever database they use, and if the vehicle description matches the auto in front of them, they do not question the VIN's authenticity.

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