Serial communication error

What does Ed (00) mean?

This error indicates a failure in serial communication. It can occur between the outdoor controller circuit board and the outdoor power circuit board, or between the outdoor controller circuit board and the M-NET board. Causes include broken wires, contact failures in connectors (CN, CNMNT, CND), defective communication circuits on the boards, or noise interference on the M-NET transmission wire.

• Serial communication failure between main control board and peripheral devices.
• Incorrect serial communication protocol setting (e.g., Baud rate, parity).
• Damaged communication wiring.
• Faulty communication interface on one of the devices.
• Interference on communication lines.

Click steps to track your progress.

1. 1

   Check the connection of connectors CN and CN between the outdoor controller circuit board and the outdoor power circuit board for disconnections or contact failures.

2. 2

   Check the connection wire between the outdoor controller circuit board (CNMNT) and the M-NET board (CN and CND) for disconnection, looseness, or breaking.

3. 3

   Review the M-NET transmission wiring method for proper installation.

4. 4

   If communication between the outdoor controller and outdoor power board fails, replace the outdoor power circuit board.

5. 5

   If communication between the outdoor controller and outdoor power board fails, replace the outdoor controller circuit board.