In CAN mode, check the 120 ohm resistor across CAN_H and CAN_L. The keypad requires it, and without it the device may work intermittently or not at all.
Check in order:
- 120 ohm resistor fitted across CAN_H and CAN_L.
- Connector pinout. Pin 2 Vin, pin 3 GND, pin 4 CAN_H, pin 5 CAN_L. Confirm CAN_H and CAN_L are not swapped.
- Mode pin at power up. Open for Run Mode. If it is grounded, the keypad starts in Utility Mode instead.
- Connector torque. The M12 connector must be tight. Maximum 14 in-lbs.
- Utility Mode check. Ground the mode pin, power up, and check the firmware version. If Utility Mode runs and Run Mode does not, it is a firmware issue, not wiring.
- Bus load. Confirm the keypad is on the correct CAN bus and the bus is terminated at both ends only.
Related: ED Keypad Wiring and Connector Pinout · ED Keypad Utility Mode and Run Mode · CAN Bus Termination and the 120 Ohm Resistor
