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the speedometer in a car does not measure
The car instrument does not display speed because the speed sensor is damaged.
Regular maintenance or replacement: The instrument of the car does not display speed because the speed sensor is damaged, and the car needs regular maintenance or parts replacement within a certain mileage interval. It is difficult to judge without mileage. After a certain mileage, the vehicle needs to be overhauled or even eliminated. There is no mileage display, so it is difficult to judge, so it can only be handled in advance.
Vehicle speed calculation:The speedometer uses the measured signal of the speed sensor to calculate and display the speed of the car. When calculating the vehicle speed, one method is to calculate the number of pulses output by the sensor in a fixed time, and the other method is to measure the time spent in a fixed pulse cycle. The method for calculating the number of pulses is that when the microprocessor detects that the number of pulses in the signal transmitted from the sensor increases, it starts to count the pulses representing the vehicle speed, and after detecting the number of pulses within the preset time, it compares the data in the counter with the data in the memory. If the difference reaches more than one kilometer per hour, the data of the counter is output to the display circuit to refresh the display value, and the whole process repeats continuously.
How:
The vehicle instrument can perform relevant operations without displaying the speed.The dashboard of a car can reflect the working conditions of various systems of the car, usually including fuel indicator, door indicator, front and rear fog indicator, etc. Automobiles are equipped with speedometer, tachometer, oil pressure gauge, fuel gauge, etc. The speedometer consists of speedometer and odometer. The traditional speedometer is mechanical and widely used in various models.The vehicle instrument does not display speed. You can adjust the return key on the right side of the multi-function steering wheel or the button on the right combination switch. For some models, you can switch back the vehicle functions by long pressing the reset key on the instrument panel. After long pressing, the display will change.The car dashboard displays no entries, which means that there is nothing on this page. It is normal. You can just call it back. For some models, long press the button on the top of the wiper until the screen shows the status of the car, and then call up the data you want.
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