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how to calibrate a speedometer
The adjustment method of the speedometer is different according to different models. It is recommended to go to the 4S store for professionals to operate. The speedometer is used to check the speed of the vehicle. It supports two units: miles per hour or kilometers per hour. The speed measurement is realized through the speed sensor. The driving speed of the vehicle is closely related to the radius of the wheel and the structure of the rotating shaft. There are two main reasons why the speed displayed by the car speedometer is larger than the actual speed: for safety reasons and errors in the calculation process.There is a maximum speed limit on the road, which is specified according to the number of accidents and the condition of the road. In order to avoid speeding and prevent car owners from overtaking. In addition, the speed measuring device on the car may have a delay. In order to avoid the instantaneous speed being too high, when the displayed value is larger than the actual value, it can prevent the car from suddenly accelerating and causing danger.
BUT:There is no way to adjust the speedometer if it is not accurate. First of all, under normal circumstances, the displayed speed of the vehicle will be about 5 km / h higher than the actual speed. This situation is very normal, and there is no need to deal with it. Secondly, if the wheel hub of the subsequently modified tire of the vehicle is not the same as the original size, the speedometer will also have a large deviation. We must not change the external dimension of the original wheel when replacing the tire hub, otherwise the error of the speedometer is very large and it is easy to cause the problem of overspeed. The speedometer is 10 kilometers slower than the actual speed. This usually happens after changing the tire or wheel hub. In fact, the outer diameter of vehicle tires will have a great impact on the vehicle speed. If we do not refer to the original factory size when replacing the wheel hub tires, the display speed will be faster than the actual speed when the outer diameter of the wheel becomes larger, and the display speed will be lower than the actual speed when the outer diameter becomes smaller. Therefore, when changing tires, we should pay attention to changing back to tires with the same size as the original factory, so as to avoid the larger outer diameter of the tire affecting the reading.
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