Daikin · Mini-split
A1 Indoor PCB defect
What this code means
The indoor unit's own circuit board has flagged an internal fault.
Most likely causes
- Board component failure
- Moisture damage to the board
- Firmware fault after a power event
What to try first
Power-cycle the unit once; if the code returns immediately, don't keep resetting it.
Safety note: if this code returns after one clean reset, stop resetting it — repeated lockouts usually mean a real fault that needs a licensed technician. Never bypass a safety switch.
FAQ
What does Daikin error code A1 mean?
Indoor PCB defect. The indoor unit's own circuit board has flagged an internal fault.
Can I fix Daikin code A1 myself?
Usually not. Power-cycle the unit once; if the code returns immediately, don't keep resetting it. If the code returns after one reset, it needs a licensed technician.
What causes Daikin code A1?
The most common causes are: board component failure; moisture damage to the board; firmware fault after a power event.
Other Daikin mini-split codes
All Daikin mini-split error codes →
Other mini-split brands: Mitsubishi · LG · Fujitsu · Gree · Carrier · Generic · Panasonic
This information may contain errors or not apply to your exact model — always double-check it against your appliance's own manual before acting. If there's any chance of a gas, fire, electrical, carbon monoxide, or other safety hazard, stop and call a licensed professional or the appropriate agency (e.g. your gas utility) instead of relying on this page alone.