OPERATION INDICATOR lamp blinks 0.5s ON/OFF — Miswiring or serial signal error

What does OPERATION INDICATOR 0.5s ON/OFF mean?

The indoor unit and outdoor unit do not operate because the serial signal from the outdoor unit has not been received for 6 minutes. This can also happen if a non-low-standby-power outdoor unit was previously connected, and a low-standby-power model is now in use. It can also be caused by miswiring or interference.

• Miswiring between indoor and outdoor units
• Serial signal communication failure from outdoor unit
• Incorrect outdoor unit model detected (low-standby-power vs. non-low-standby-power)
• Poor contact or wire disconnection in indoor/outdoor connecting wire
• Interference from inverter-controlled lighting equipment

Click steps to track your progress.

1. 1

   Turn OFF the power supply to the unit at the circuit breaker, wait for a few minutes, then turn it back ON.

2. 2

   Press the emergency operation switch on the indoor unit.

3. 3

   Turn OFF any inverter-controlled lighting equipment nearby, or re-position the unit/light to reduce interference.

4. 4

   Check all indoor/outdoor connecting wires for miswiring, damage, or poor contact.

5. 5

   If a low-standby-power model is now connected, clear the error history by referring to 'Deleting the memorized abnormal condition' (10-2.1) in the full manual.

6. 6

   Refer to the 'How to check miswiring and serial signal error' section (10-6) in the full manual for detailed checks.