Fujitsu fault codes
47 documented codes for Fujitsu mini-splits, each cited to the manufacturer's own manual. Fujitsu General builds the Halcyon (now AIRSTAGE) mini-split line sold in the US and Canada under both the Fujitsu and General names. Every R410A/R32 mini-split generation from the RL2/RLS2/RLS3/RLB/RLXB/RLF/RGLX era through the current LMAS/LZAS/LPAS/LUAS1 series uses the SAME two-number fault system: the OPERATION lamp blinks the first digit and the TIMER lamp blinks the second digit (while the ECONOMY lamp blinks fast/continuously), and the same number appears as a two-character code (11, 12, 41, A1, J2) on a wired remote controller. Older units (RLS, RLXS, CQ, RQ, R2, RL, RML, RMLQ, CLX, RLX, RLXQ, CL, RLQ) use a DIFFERENT blink-to-fault mapping for the same faults; those alternate patterns are recorded in each code's notes field.. Sold as Fujitsu General Halcyon and AIRSTAGE in North America.
Mini-Split codes
| Code | Meaning | Severity |
|---|---|---|
| 11OPERATION lamp blinks 1 time, TIMER lamp blinks 1 time, ECONOMY lamp blinking continuously/fast | Serial communication error | Soft lockout |
| 12OPERATION lamp blinks 1 time, TIMER lamp blinks 2 times, ECONOMY lamp blinking continuously | Wired remote controller communication error | Soft lockout |
| 15OPERATION lamp blinks 1 time, TIMER lamp blinks 5 times, ECONOMY lamp blinking continuously | On multi-zone | Warning |
| 18OPERATION lamp blinks 1 time, TIMER lamp blinks 8 times, ECONOMY lamp blinking continuously | External communication error | Soft lockout |
| 21OPERATION lamp blinks 2 times, TIMER lamp blinks 1 time, ECONOMY lamp blinking continuously | Number of wires and pipes error on a multi-zone system | Soft lockout |
| 22OPERATION lamp blinks 2 times, TIMER lamp blinks 2 times, ECONOMY lamp blinking continuously | Indoor unit capacity error on a multi-zone system | Soft lockout |
| 23OPERATION lamp blinks 2 times, TIMER lamp blinks 3 times, ECONOMY lamp blinking continuously | Combination error | Hard lockout |
| 24OPERATION lamp blinks 2 times, TIMER lamp blinks 4 times, ECONOMY lamp blinking continuously | Number of indoor units error or number of branch boxes error | Soft lockout |
| 26OPERATION lamp blinks 2 times, TIMER lamp blinks 6 times, ECONOMY lamp blinking continuously | Address setting error in the wired remote controller system | Soft lockout |
| 29OPERATION lamp blinks 2 times, TIMER lamp blinks 9 times, ECONOMY lamp blinking continuously | Connection unit number error | Soft lockout |
| 32OPERATION lamp blinks 3 times, TIMER lamp blinks 2 times, ECONOMY lamp blinking continuously | Indoor unit model information error / EEPROM access abnormal | Hard lockout |
| 33OPERATION lamp blinks 3 times, TIMER lamp blinks 3 times, ECONOMY lamp blinking continuously | Indoor unit motor electricity consumption detection error | Soft lockout |
| 35OPERATION lamp blinks 3 times, TIMER lamp blinks 5 times, ECONOMY lamp blinking continuously | Manual auto switch error | Warning |
| 39OPERATION lamp blinks 3 times, TIMER lamp blinks 9 times, ECONOMY lamp blinking continuously | Indoor fan motor power supply error | Soft lockout |
| 3AOPERATION lamp blinks 3 times, TIMER lamp blinks 10 times, ECONOMY lamp blinking continuously | Indoor unit communication circuit | Soft lockout |
| 41OPERATION lamp blinks 4 times, TIMER lamp blinks 1 time, ECONOMY lamp blinking continuously | Indoor room thermistor error | Soft lockout |
| 42OPERATION lamp blinks 4 times, TIMER lamp blinks 2 times, ECONOMY lamp blinking continuously | Indoor heat exchanger | Soft lockout |
| 44OPERATION lamp blinks 4 times, TIMER lamp blinks 4 times, ECONOMY lamp blinking continuously | Human sensor error | Warning |
| 51OPERATION lamp blinks 5 times, TIMER lamp blinks 1 time, ECONOMY lamp blinking continuously | Indoor unit fan motor error | Soft lockout |
| 53OPERATION lamp blinks 5 times, TIMER lamp blinks 3 times, ECONOMY lamp blinking continuously | Drain pump error | Warning |
| 57OPERATION lamp blinks 5 times, TIMER lamp blinks 7 times, ECONOMY lamp blinking continuously | Damper error | Warning |
| 58OPERATION lamp blinks 5 times, TIMER lamp blinks 8 times, ECONOMY lamp blinking continuously | Intake grille error | Warning |
| 62OPERATION lamp blinks 6 times, TIMER lamp blinks 2 times, ECONOMY lamp blinking continuously | Outdoor unit main PCB error | Hard lockout |
| 63OPERATION lamp blinks 6 times, TIMER lamp blinks 3 times, ECONOMY lamp blinking continuously | Inverter error | Hard lockout |
| 64OPERATION lamp blinks 6 times, TIMER lamp blinks 4 times, ECONOMY lamp blinking continuously | PFC circuit error or active filter error, depending on model | Hard lockout |
| 65OPERATION lamp blinks 6 times, TIMER lamp blinks 5 times, ECONOMY lamp blinking continuously | IPM | Hard lockout |
| 6AOPERATION lamp blinks 6 times, TIMER lamp blinks 10 times, ECONOMY lamp blinking continuously | Display PCB communication error | Hard lockout |
| 71OPERATION lamp blinks 7 times, TIMER lamp blinks 1 time, ECONOMY lamp blinking continuously | Discharge thermistor error | Soft lockout |
| 72OPERATION lamp blinks 7 times, TIMER lamp blinks 2 times, ECONOMY lamp blinking continuously | Compressor thermistor error | Soft lockout |
| 73OPERATION lamp blinks 7 times, TIMER lamp blinks 3 times, ECONOMY lamp blinking continuously | Heat exchanger | Soft lockout |
| 74OPERATION lamp blinks 7 times, TIMER lamp blinks 4 times, ECONOMY lamp blinking continuously | Outdoor thermistor error | Soft lockout |
| 75OPERATION lamp blinks 7 times, TIMER lamp blinks 5 times, ECONOMY lamp blinking continuously | Suction gas thermistor error | Soft lockout |
| 76OPERATION lamp blinks 7 times, TIMER lamp blinks 6 times, ECONOMY lamp blinking continuously | 2-way or 3-way valve thermistor error | Soft lockout |
| 77OPERATION lamp blinks 7 times, TIMER lamp blinks 7 times, ECONOMY lamp blinking continuously | Heat sink thermistor error | Soft lockout |
| 82OPERATION lamp blinks 8 times, TIMER lamp blinks 2 times, ECONOMY lamp blinking continuously | Sub-cool heat exchanger gas inlet or gas outlet thermistor error | Soft lockout |
| 83OPERATION lamp blinks 8 times, TIMER lamp blinks 3 times, ECONOMY lamp blinking continuously | Liquid pipe thermistor error | Soft lockout |
| 84OPERATION lamp blinks 8 times, TIMER lamp blinks 4 times, ECONOMY lamp blinking continuously | Current sensor error | Soft lockout |
| 86OPERATION lamp blinks 8 times, TIMER lamp blinks 6 times, ECONOMY lamp blinking continuously | High pressure switch error, or on 42k and 48k units a pressure sensor error | Soft lockout |
| 94OPERATION lamp blinks 9 times, TIMER lamp blinks 4 times, ECONOMY lamp blinking continuously | Over current error | Soft lockout |
| 95OPERATION lamp blinks 9 times, TIMER lamp blinks 5 times, ECONOMY lamp blinking continuously | Compressor motor control error | Hard lockout |
| 97OPERATION lamp blinks 9 times, TIMER lamp blinks 7 times, ECONOMY lamp blinking continuously | Outdoor unit fan motor error | Soft lockout |
| 98OPERATION lamp blinks 9 times, TIMER lamp blinks 8 times, ECONOMY lamp blinking continuously | Outdoor unit fan motor 2 error, on twin-fan condensers | Hard lockout |
| 99OPERATION lamp blinks 9 times, TIMER lamp blinks 9 times, ECONOMY lamp blinking continuously | 4-way | Soft lockout |
| A1OPERATION lamp blinks 10 times, TIMER lamp blinks 1 time, ECONOMY lamp blinking continuously | Discharge temperature error | Soft lockout |
| A3OPERATION lamp blinks 10 times, TIMER lamp blinks 3 times, ECONOMY lamp blinking continuously | Compressor temperature error | Soft lockout |
| A5OPERATION lamp blinks 10 times, TIMER lamp blinks 5 times, ECONOMY lamp blinking continuously | Low pressure error | Soft lockout |
| J2OPERATION lamp blinks 13 times, TIMER lamp blinks 2 times, ECONOMY lamp blinking continuously | Branch box error | Soft lockout |
Looking it up by flash count?
If you counted LED flashes rather than reading a code number, start here:
Manuals used for this page
- 410A Mini-Split Troubleshooting Guide (Part # 6-26-FG2020 Rev. 5/2019) (Fujitsu General America, Inc.) · checked 2026-08-25
- Operating Manual - Air Conditioner Wall Mounted Type (PART No. 9315345615) (Fujitsu General Limited) · checked 2026-08-25
- Operation Manual - Air Conditioner Wall Mounted Type (PART No. 9387602173-02 family) (Fujitsu General Limited) · checked 2026-08-25
- Communication Error - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- Indoor Fan Motor Error - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- Drain Pump Error - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- Outdoor Fan Motor Error - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- Over Current Error (Trip Detection) - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- Compressor Control / Compressor Location Error - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- 4-Way Valve Error - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- Discharge Temperature Error - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- Compressor Temperature Error - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- 2-Way / 3-Way Valve Thermistor Error - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- Check-run Unfinished - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- Indoor Capacity Error - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25
- S Bulletin 044 - A5 Error Code - Fujitsu General Help Center (Fujitsu General America, Inc.) · checked 2026-08-25