Mitsubishi · Mini-split
E1 Indoor PCB error
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
What to try first
Power-cycle once; a recurring E1 needs the board inspected by a technician.
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 Mitsubishi error code E1 mean?
Indoor PCB error. The indoor unit's own circuit board has flagged an internal fault.
Can I fix Mitsubishi code E1 myself?
Usually not. Power-cycle once; a recurring E1 needs the board inspected by a technician. If the code returns after one reset, it needs a licensed technician.
What causes Mitsubishi code E1?
The most common causes are: board component failure; moisture damage to the board.
Other Mitsubishi mini-split codes
All Mitsubishi mini-split error codes →
Other mini-split brands: Daikin · 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.