Fault phenomena:
After measuring the vehicle with a four-wheel aligner, it is found that the tilt angle can be displayed normally, but the front beam cannot be displayed.

Analysis of faults:
1) Detect whether there are obstacles in the chassis to block the connection of the CCD spot.
2) Whether there are impurities on the protective lens of the sensor CCD transmitting light points to block the transmission of light points.
3) Whether the secondary light emitting tube of sensor CCD is damaged or not.
4) Whether the CCD of the sensor is damaged or not.
5) Whether the motherboard is damaged or not.

Judging faults and solving methods:
1) First, check whether there are obstacles in the chassis of the car, and if there are obstacles, remove them.
2) Clean 8 lenses of 4 sensors with a clean towel.
3) Watch if there is a CCD light shield on the display that indicates the number of sensors. If there is, check if there is a red light on the CCD diode of the relevant sensor. If not, replace it.
4) Take a new or removed CCD from other good sensors and replace the CCD of the faulty sensor. If the problem is good, it means the problem of CCD.
5) Replace the motherboard.