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my speedometer is off
Reasons for the speedometer is off:
1. The speedometer needle is unstable. The reason is that the flexible shaft is defective, the watch is damaged or the flexible shaft locking nut is not installed properly. The flexible shaft, watch and watch should be replaced or the installation method of the flexible shaft nut should be changed;
2. Check that the sensor is damaged so that the car tachometer does not go. The needle of the car tachometer is stuck, causing the car tachometer not to go;
3:The speedometer failed. The reason is that the flexible shaft is damaged, the watch is damaged or the connecting nut of the flexible shaft is not tightened, and the flexible shaft, watch or flexible shaft tightening nut should be replaced.
4.First, check whether the speedometer flexible shaft lock nut is installed properly, then remove both ends of the flexible shaft, and twist both ends of the mandrel by hand. If there is a feeling that the resistance is large or small, the steel wire mandrel is bent, and a new mandrel or flexible shaft should be replaced; if the resistance is uniform and there is no stickiness, check whether the odometer drum is a card issuing, if it is a card, replace it, otherwise replace the mileage surface.
How:
1. First check whether the connection of the flexible shaft is disconnected, and then see if the mileage is starting to increase. If only the speedometer does not move, it can only be replaced with a new one;
2. Another possibility is that there is a foreign object in the meter that is stuck and cannot be moved. Open the meter to clear the foreign object and then move it;
The car speedometer does not move, it is generally a problem of sharing the ground wire, and everything else is normal is a small problem. But to be on the safe side, it's better to go to the repair point and check it out. The speedometer will directly read the received digital pulse signal (sent from the sensor) into the counting port of the cpu after processing, calculate the rotational speed and the corresponding position of the pointer through the software, and then drive the stepper motor through the control port of the cpu after amplification. Rotate in positive and negative directions, indicating the corresponding speed value (the pointer is directly installed on the rotating shaft of the stepping motor), and the stepping motor takes only 1/3 of a degree.
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