Fault phenomena:
1.One or four sensors charged the electricity overnight, but the next day, just made a car and found that four sensors were dead!
2.Two or four sensors are also charged together, but in the process of using, the other three still have electricity, only one has no electricity!

Analysis of faults:
1.Check the stability of the switching power supply.
2.Check if the charging line is broken.
3.Check whether the sensor terminal is loose or not in good contact.
4.Check the stability of the battery
5.Check the stability of the motherboard.

Judging faults and solving methods:
Observing whether the four sensors work in the same way, if they are not charged, if the other three are good, it means that the switching power supply is not a problem. If the four sensors cannot be charged, it means that 80% may be caused by the switching power supply, or if there is a multi-meter, the multi-meter can be used to measure the voltage.

Check carefully whether the charging line is broken or exposed from the beginning.

If the middle plastic cover and other sensors can be exchanged and charged normally, it means that there is a problem with the terminal on the middle plastic shell. If the same reaction does not occur after the exchange, then the problem of the terminal will be eliminated.

If the battery on the sensor is interchanged with the battery of other sensors, if the problem of failure is solved after interchange, then it is the battery fault. If there is no reaction after interchange, the possibility of failure caused by the battery is eliminated.
If the above reasons are excluded, then it is basically the problem of the sensor motherboard.