English 
why is my speedometer off
Speedometer:
It indicates the speed of the vehicle. It shows the instantaneous speed, which is why the pointer shakes. You will understand the principle of the speedometer below.The indication of the speedometer depends on the speed sensor. The sensor is installed on the gearbox. Different pulse signals are obtained through different speeds, and then converted to pointer output, which is the current speed you see. The regulations require the speedometer to display slightly higher than the actual speed, which is for safety. Another is the liquid crystal display speed. The principle is similar to the above, and the indication output is replaced by liquid crystal display.
Why is the speedometer off:
The first is the odometer sensor failure.
The second is that there is a problem with the circuit between the instrument and the sensor.
The third is that the instrument pointer fails.
How to check speedometer:
(1) Check whether all visible parts of the system are abnormal, whether the conductor is peeled off and whether the vacuum hose is damaged. All hoses shall be shunted correctly and connected firmly;
(2) The speedometer cord must also be correctly placed, and shall not be excessively bent or twisted together. The joint shall be firm;
(3) Servo mechanism (i.e. throttle actuator) and pull rod shall work smoothly;
(4) The empty stroke of the traction chain shall not be greater than 1 / 4 inch;
(5) Electrical connectors must be complete and firm;
(6) The wire harness must be neat and not plain. Check whether there is insulation peeling and whether the connector is loose or short circuited; make the above necessary corrections before continuing other inspections.
The method of replacing the speedometer is as follows: If the prepared flexible shaft needs to be installed on the tachometer, first remove the old flexible shaft from the speedometer. If the inner shaft can be pulled out of the casing, it means that the old flexible shaft has been broken, and the flexible shaft casing should be removed from the gearbox in order to remove the broken flexible shaft. After the old flexible shaft is removed, apply a thin layer of speedometer flexible shaft grease evenly on the two-thirds of the lower end of the flexible shaft. Do not wipe the entire flexible shaft, otherwise grease will flow into the meter head along the flexible shaft, causing damage.
Get a Quote / Info