... and some keys do not work?
- Check cable installation
The cable must go through the left hole.
Using the right hole could restrict the movement of some keys.
- Check keypad PINs on the PCB
The keypad integrated in the plastic cover is connected through several connectors (X4, X5, X15 and X16) to the PCB.
If these pins are damaged/bent, then the keypad can not be properly connected.