Fujitsu Minisplit Error Codes

All Fujitsu minisplit error codes with step-by-step troubleshooting, multimeter specs, and OEM part numbers.

4 error codes

Code	Meaning	Severity	Difficulty
A1	A1 on a Fujitsu Halcyon mini-split means the indoor unit printed circuit board (PCB) has detected an internal fault. The control board manages all indoor unit functions including fan control, temperature sensing, and communication with the outdoor unit. highadvanced	high	advanced
HUB	Fujitsu Halcyon mini-split systems display single or double-letter fault codes on the indoor unit display when a component failure or sensor fault is detected. These codes help identify whether the issue is in the indoor unit, outdoor unit, or communication between the two. lowbeginner	low	beginner
NOT-COOLING	Causes and Fixes mediumintermediate	medium	intermediate
NOT-HEATING	Causes and Fixes mediumintermediate	medium	intermediate