Pick up and tear off the black trademark on the display board with a knife, remove the screw that fixes the display board, remove the display board and unplug the bus bar. Use a multimeter to put one end on the bus bar where the display panel is not plugged in, and the other end on the bus bar at the upper end of the door body, and check the resistance according to the color.

It is suggested that it is best not to dismantle it yourself, so that professional after-sales maintenance can be carried out.