Daikin Mini Split Error Code AJ: How to Fix It

Q: What does Daikin error code AJ mean?

Error AJ indicates a capacity setting abnormality, meaning the DIP switch settings for capacity do not match between indoor and outdoor units or are invalid.

Q: How do I reset Daikin error AJ?

Turn off power for 10 minutes, then restore. If the error persists, you must correct the capacity DIP switch settings.

Q: Can a faulty PCB cause error AJ?

Yes, if DIP switches are set correctly but error persists, a faulty indoor or outdoor PCB may be the cause.

Q: Where are the DIP switches on a Daikin mini split?

On the indoor unit, they are on the main PCB behind the front panel. On the outdoor unit, they are on the outdoor PCB accessed by removing the side panel.

Q: Is error AJ serious?

It prevents the system from operating correctly but is not a safety hazard. However, ignoring it can lead to improper cooling/heating.

Abstract

Daikin error code AJ indicates a capacity setting abnormality. This typically means the indoor unit capacity dip switch settings don't match the outdoor unit or are improperly configured. This guide will help you identify and correct the settings.