Function Purpose：An odometer is a device in vehicles used to record the total distance the vehicle has traveled. It shows the cumulative mileage since the vehicle left the factory, allowing the owner and relevant personnel to understand the usage and driving conditions of the vehicle, which is of great significance for vehicle maintenance, value assessment and other aspects.
Working Principle：
Mechanical Odometer：It works mainly through a mechanical gear transmission device. Every time the vehicle's wheel rotates one circle, it will transmit the rotation to the odometer through a series of gear mechanisms. The digital wheel in the odometer will then rotate a certain angle accordingly, thus displaying the driving mileage. For example, the rotation of the wheel drives the gear on the axle to rotate, and this gear meshes with the gear in the odometer to convert the rotation of the wheel into the change of numbers.
Electronic Odometer：It uses electronic sensors to measure the rotation of the wheels. The sensor converts each rotation of the wheel into an electrical signal, and these electrical signals are transmitted to the vehicle's electronic control unit (ECU). The ECU processes and calculates these signals and then displays the accurate mileage on the odometer display. For instance, a Hall effect sensor can generate electrical signals based on the change of the magnetic field near the wheel to record the number of wheel rotations.
Benefits：
Recording Driving Mileage：The most important function is to accurately record the total mileage of the vehicle, which is very important for the owner to understand the vehicle's usage, judge the degree of wear and tear of the vehicle and arrange the maintenance plan. For example, general cars need to be maintained every certain mileage, and the odometer reading is an important basis for determining the maintenance time.
Vehicle Value Evaluation：In the used car trading, the mileage shown on the odometer is one of the key factors in evaluating the value of the vehicle. Usually, the vehicle with lower mileage has less wear and tear and is relatively more valuable.
Data Analysis and Management：For fleet management and other situations, odometer data can help managers understand the vehicle's usage frequency, driving routes and other information, so as to carry out reasonable scheduling and management, and can also be used to statistically analyze the vehicle's operating costs and so on.
Related Regulations and Norms：In many countries and regions, there are laws and regulations regarding odometers. For example, it is prohibited to tamper with odometer data, because this will seriously affect the fairness and safety of vehicle transactions. If someone is found to deliberately tamper with the odometer, they may face legal liability and punishment.
