There is no driving wave output at each output pin of 1. circuit. Press the LCD connector with your finger and observe whether the strokes that should be displayed are displayed. If the contact is poor or the tablet is not tightly pressed, the screw should be rotated again.

2. The conductive rubber has poor contact with the LCD screen or circuit board. Check whether there is dust or stain on the driving end corresponding to the stroke not shown, and wipe the conductive rubber with gauze soaked in absolute alcohol.

3. Disjoint or virtual welding between solder joint and circuit. If the connecting rubber is bent or stretched, the conductive rubber should be replaced, and if the electrodes of the display screen are damaged, the display screen should be replaced.

4. Use a multimeter to check whether there is voltage on the line that does not display strokes, and then put the movement into the case.