Odometer tampering - a scam targeting used car buyers.
By using diagnostic equipment, sellers can make customers think that a car has been used sparingly and is still in good condition.
When buying a used car, the general mindset is that the lower the mileage, the better the remaining quality, and they are willing to pay a higher price. Taking advantage of this belief, some sellers intentionally tamper with the odometer to deceive buyers. There are also cases where the odometer is tampered with objectively due to repairs, replacements, or because the car has had multiple previous owners who tampered with it, making the subsequent owner unaware of its history.
The most common situation nowadays is with cars imported from abroad. For non-officially imported cars, dealerships cannot bring them into the country if they are new. To import them, the cars must be used vehicles that have been driven for at least 6 months or have traveled over 10,000 km. Therefore, the cars are "magically" transformed into used cars by tampering with the odometer.
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In reality, tampering with odometers carries many risks because a simple inspection by an authorized dealer can easily detect whether it has been tampered with. However, for cars that have been used for a short time but have excessive mileage, sellers still resort to tampering to make the vehicle's records look better. More importantly, the customer's preference for low-mileage vehicles remains the key factor.
So how is odometer tampering done?
For mechanical watches
The seller will disassemble the circuit board and adjust it manually. This type of work is mainly found on older cars and is quite rare to find.
For electronic watches
To perform an electronic engine overhaul, a tool is needed to access the vehicle's ECU. The process is quite simple: just connect the tool to the ECU via the connector located at the bottom of the ECU, and the computer will handle the rest. The ECU's location varies depending on the vehicle; it could be behind the dashboard near the instrument cluster, in the glove compartment, under the left driver's seat, or in the engine compartment.
Rewinding an electronic odometer using a machine.
According to Vietnamese mechanics, most car brands can have their odometers tampered with, with only a few models being impossible to tamper with. Most cars that cannot be tampered with are luxury or rare vehicles because purchasing the license to unlock them is expensive. In Vietnam, the Cadillac Escalade is almost the only model that cannot be tampered with. Each type of car requires a specific wiring harness for connection. The cost of a tampering machine is around tens of millions of Vietnamese dong, and the cost of a single tampering operation ranges from 300,000 to 1,500,000 dong depending on the car model and difficulty.
In fact, besides changing the odometer reading, the odometer adjuster has many other functions such as: calibrating the radio, programming the airbag warning lights, identifying engine faults, and setting up some electronic functions on the vehicle.
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How can you detect if the odometer has been tampered with?
For luxury cars, simply plugging in a diagnostic tool will reveal the old odometer reading. However, this is much more difficult for mainstream cars unless they are under manufacturer's warranty.
How can buyers of used cars tell if the odometer has been tampered with?
- Look at the degree of wear and tear on the interior to assess the situation. For example, if the mileage is low but the leather seats are heavily worn and torn, it's very likely the odometer has been tampered with.
- Car lights: brightness of the lights, whether the headlight housing is new or old.
- Tires: For cars under 3 years old, even if the tires have been replaced but the mileage is only 20,000-30,000 km, it's highly likely that the odometer has been tampered with. Tires only need replacing after 50,000 km.
- Test drive: driving to check the rigidity of the chassis and the sturdiness of the connections between the components.
- Go to a reputable, authorized garage for inspection.
In reality, the odometer reading doesn't always accurately reflect a car's quality; it's just an indicator for reference and monitoring its condition. A car that's driven a lot but regularly maintained and well-cared for can be in better condition than one that's driven less but neglected by its owner. In the US, there are cars that have driven over one million miles (more than 1.6 million km) and are still running well.