Upper lamp blinks 4 times - Indoor control system memory issue

What does 4-time blink (2.5-second OFF) mean?

The upper operation indicator lamp blinks four times with a 2.5-second pause. This indicates the indoor electronic control P.C. board cannot properly read data from its non-volatile memory.

• Faulty indoor electronic control P.C. board
• Memory corruption on the control board
• Electrical interference affecting the board

Click steps to track your progress.

1. 1

   Replace the indoor electronic control P.C. board.

2. 2

   Note: An 'EE' error might also be detected for the outdoor unit.

3. 3

   If units are compatible, prioritize addressing the 'Fb' error (if present).