When your Samsung system stops and shows a code, that code is the system telling you roughly where the problem is. Roughly is the key word. A fault code points in a direction, it rarely names the exact fix. Find your system below, tap your code, and it will take you straight to what it means and what to do.
Before you try anything: the only DIY steps that are ever safe are switching the system off at the isolator (and waiting 20 to 30 minutes), cleaning or checking filters, checking the controller settings and batteries, and keeping the outdoor unit clear. Anything behind a panel, anything electrical, and anything involving refrigerant or gas is licensed work. If a code below says switch off and call, please take it at its word.
How to read the tables: 🟢 means there is a safe first step worth trying. 🟡 means book a service, the system needs a technician. 🔴 means switch the system off at the isolator and call us on (02) 4760 0100.
Wall-mounted splits without a code display (status-LED models)
Where the code shows: Indoor unit status LEDs read left to right: LED1 = Operation, LED2 = Timer, LED3 = S-Plasma Ion. Patterns below are LED1-LED2-LED3 (OFF / BLINK / ON). Outdoor faults also show a pattern on the outdoor PCB LEDs..
Tap your code: OFF-BLINK-BLINK (indoor LEDs)OFF-BLINK-OFF (indoor LEDs)BLINK-BLINK-OFF (indoor LEDs)BLINK-OFF-BLINK (indoor LEDs)OFF-OFF-BLINK (indoor LEDs)ON-BLINK-BLINK (outdoor LEDs)BLINK-OFF-BLINK (outdoor LEDs)BLINK-BLINK-OFF (outdoor LEDs)BLINK-OFF-ON (outdoor LEDs)ON-OFF-OFF (outdoor LEDs)ON-OFF-ON (outdoor LEDs)OFF-ON-BLINK (outdoor LEDs)ON-BLINK-ON (outdoor LEDs)BLINK-ON-OFF (outdoor LEDs)OFF-ON-OFF / ON-OFF-BLINK (outdoor LEDs)ON-ON-BLINK (outdoor LEDs)BLINK-OFF-OFF (outdoor LEDs)ON-ON-OFF (outdoor LEDs)OFF-OFF-BLINK (outdoor LEDs)ALL indoor LEDs flashing
| Code | What it means | What to do |
|---|---|---|
| OFF-BLINK-BLINK (indoor LEDs) | The indoor and outdoor units have stopped talking to each other. Communication error. Outdoor PCB may show BLINK-ON-ON (1-minute comms timeout) or OFF-OFF-ON / OFF-ON-ON (abnormal communication). |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the pattern comes back, book a service. |
| OFF-BLINK-OFF (indoor LEDs) | The indoor unit's room temperature sensor isn't reading properly. Indoor room temperature sensor error. |
🟡 Book a service call – this one needs a technician. |
| BLINK-BLINK-OFF (indoor LEDs) | The indoor coil's temperature sensor isn't reading properly. Indoor heat exchanger (eva-in) temperature sensor error. |
🟡 Book a service call – this one needs a technician. |
| BLINK-OFF-BLINK (indoor LEDs) | The indoor unit is reporting a fault in the outdoor unit – the outdoor unit's own LEDs show which one. Generic 'outdoor error' signal shown on the indoor unit for all outdoor-side faults in this range. |
🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the pattern returns, book a service. |
| OFF-OFF-BLINK (indoor LEDs) | The indoor fan motor isn't spinning at the speed it should. Indoor BLDC fan motor speed detection error. |
🟡 Book a service call – this one needs a technician. |
| ON-BLINK-BLINK (outdoor LEDs) | The voltage sensor on the outdoor unit's inverter board isn't reading properly. DC-link voltage sensor error. |
🟡 Book a service call – this one needs a technician. |
| BLINK-OFF-BLINK (outdoor LEDs) | The outdoor air temperature sensor isn't reading properly. Outdoor temperature sensor error. |
🟡 Book a service call – this one needs a technician. |
| BLINK-BLINK-OFF (outdoor LEDs) | The compressor discharge temperature sensor isn't reading properly. Outdoor discharge temperature sensor error. |
🟡 Book a service call – this one needs a technician. |
| BLINK-OFF-ON (outdoor LEDs) | The compressor got too hot and the unit shut itself down to prevent damage. Outdoor discharge over-temperature protection. Can point to low refrigerant. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| ON-OFF-OFF (outdoor LEDs) | The outdoor fan motor isn't running properly. Outdoor fan motor error. |
🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays. |
| ON-OFF-ON (outdoor LEDs) | The outdoor unit can't drive the compressor properly – a compressor wiring or rotation fault. Compressor wire missing / rotation error. |
🟡 Book a service call – this one needs a technician. |
| OFF-ON-BLINK (outdoor LEDs) | The power supply to the outdoor unit went outside its safe voltage range and the unit protected itself. DC-link voltage under/over error, over-voltage protection, or PFC overload. |
🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the pattern returns, book a service. |
| ON-BLINK-ON (outdoor LEDs) | The unit tripped on an electrical over-current and shut itself down. I-trip error / PFC over-current. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| BLINK-ON-OFF (outdoor LEDs) | The outdoor unit is limiting the compressor because voltage or current went out of range. Compressor V-limit / current-limit error. |
🟡 Book a service call – this one needs a technician. |
| OFF-ON-OFF / ON-OFF-BLINK (outdoor LEDs) | The outdoor unit's control board has a memory fault. EEPROM error (OFF-ON-OFF) or OTP error (ON-OFF-BLINK). |
🟡 Book a service call – this one needs a technician. |
| ON-ON-BLINK (outdoor LEDs) | The unit can't read the incoming mains power waveform properly. AC zero-cross signal error. |
🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the pattern returns, book a service. |
| BLINK-OFF-OFF (outdoor LEDs) | The indoor and outdoor units aren't a matching capacity pairing. Capacity mismatch error. |
🟡 Book a service call – this one needs a technician. |
| ON-ON-OFF (outdoor LEDs) | The system thinks it has lost refrigerant. Gas leak error. |
🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician. |
| OFF-OFF-BLINK (outdoor LEDs) | The inverter power module tripped on over-current and shut the unit down. IPM over-current (O.C.). |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| ALL indoor LEDs flashing | The indoor unit's model option code hasn't been set correctly. Option code error – all LEDs flash on the indoor unit. |
🟡 Book a service call – this one needs a technician. |
Four-way cassette range (outdoor unit E-codes)
Where the code shows: Outdoor unit PCB LED display (red/green/yellow LEDs on the MAIN and INVERTER boards), reported as E-codes..
Tap your code: E201E202E203E221E231E251E320E403E404E416E440E441E458E475E461E462E463E464E465E466E467E468E471E474E484E500E554E556E557
| Code | What it means | What to do |
|---|---|---|
| E201 | The outdoor unit can't see the number of indoor units it expects. Indoor/outdoor unit quantity mismatch – usually an addressing or setup issue. |
🟡 Book a service call – this one needs a technician. |
| E202 | The indoor and outdoor units have stopped talking to each other. Indoor-outdoor communication error. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E203 | The outdoor unit's two circuit boards (main and inverter) have lost communication with each other. Main-inverter communication timeout (1 minute). |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E221 | The outdoor air temperature sensor isn't reading properly. Outdoor temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E231 | The outdoor coil (condenser) temperature sensor isn't reading properly. Condenser temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E251 | The compressor discharge temperature sensor isn't reading properly. Discharge temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E320 | The compressor's overload-protection temperature sensor isn't reading properly. OLP sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E403 | The system detected freezing at the outdoor unit and stopped the compressor to protect itself. Outdoor freeze detection while compressor stopped. |
🟡 Check the return-air filters are clean and nothing is blocking the outdoor unit, then book a service if the code stays. |
| E404 | The outdoor unit shut down to protect itself from overloading. Outdoor overload protection while compressor stopped. |
🟡 Check nothing is blocking airflow around the outdoor unit, then book a service if the code stays. |
| E416 | The compressor got too hot and the system shut down to prevent damage. Compressor discharge over-temperature. Can point to low refrigerant. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E440 | Heating is locked out because the outdoor temperature is above about 30 degrees C. Heating-mode ambient lockout, not a component failure. |
🟢 Check the unit is in the mode you actually want. Heating resumes once the outdoor temperature drops back into range – book a service only if it persists in cool weather. |
| E441 | Cooling is locked out because the outdoor temperature is below about -5 degrees C. Cooling-mode ambient lockout, not a component failure. |
🟢 Check the unit is in the mode you actually want. Cooling resumes once the outdoor temperature rises back into range – book a service only if it persists in warm weather. |
| E458 | Outdoor fan 1 isn't running properly. Outdoor BLDC fan 1 error. |
🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays. |
| E475 | Outdoor fan 2 isn't running properly. Outdoor BLDC fan 2 error. |
🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays. |
| E461 | The compressor is failing to start. Inverter compressor starting error. |
🟡 Book a service call – this one needs a technician. |
| E462 | The unit shut down because it drew too much electrical current. Primary current trip error. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E463 | The unit tripped on an electrical over-current and shut itself down. Over-current trip / PFC over-current error, remark 'check OLP sensor'. Samsung's own manuals also describe E463 as the compressor's overload protector (OLP) overheating and stopping the compressor – the same protective trip worded two ways. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E464 | The inverter power module tripped on over-current and shut the unit down. IPM (IGBT module) over-current. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E465 | The compressor overloaded and the unit shut down to protect it. Compressor overload error as printed; Samsung manuals elsewhere call the same code the compressor V-limit (voltage-limit) error – same protection. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E466 | The power supply to the unit went outside its safe voltage range. DC-link voltage under/over error – often follows a power glitch or brownout. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E467 | The outdoor unit can't drive the compressor properly – a compressor wiring or rotation fault. Compressor wire missing error. |
🟡 Book a service call – this one needs a technician. |
| E468 | A current sensor on the outdoor unit's electronics isn't reading properly. Current sensor error on the inverter board. |
🟡 Book a service call – this one needs a technician. |
| E471 | The outdoor unit's control board has a memory fault. Outdoor EEPROM error. |
🟡 Book a service call – this one needs a technician. |
| E474 | A temperature sensor on the inverter electronics isn't reading properly. IPM (IGBT module) or PFCM temperature sensor error. |
🟡 Book a service call – this one needs a technician. |
| E484 | The power-correction circuit in the outdoor unit overloaded and shut the unit down. PFC overload error. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E500 | The inverter electronics overheated and the unit shut down to protect itself. IPM over-heated. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E554 | The system thinks it has lost refrigerant. Gas leak error. |
🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician. |
| E556 | The indoor and outdoor units aren't a matching capacity pairing. Capacity mismatch between indoor and outdoor unit. |
🟡 Book a service call – this one needs a technician. |
| E557 | The indoor units' option codes don't match each other. Option code mismatch among indoor units (DPM only). |
🟡 Book a service call – this one needs a technician. |
Wired remote controller codes (cassette and ducted systems)
Where the code shows: Wired remote controller screen – a warning icon appears, press the Test button to show the numeric code..
Tap your code: 101102121122128129153201202203221231237251320403404416419422425440441458460461462463464465466467468469471472473474475484485500554556557601602606EA
| Code | What it means | What to do |
|---|---|---|
| 101 | The controller has lost communication with the indoor unit. Indoor unit communication error. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| 102 | The indoor and outdoor units have stopped talking to each other. Indoor-outdoor communication timeout (more than 6 bad packets / 60-packet over-data). |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| 121 | The indoor unit's room temperature sensor isn't reading properly. Indoor temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| 122 | The indoor coil's temperature sensor isn't reading properly. Indoor eva-in pipe sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| 128 | The indoor coil sensor has come loose from its mounting. Eva-in sensor disconnection/separation. |
🟡 Book a service call – this one needs a technician. |
| 129 | The indoor coil outlet sensor has come loose from its mounting. Eva-out sensor separation. |
🟡 Book a service call – this one needs a technician. |
| 153 | The condensate drain system has flagged high water – the drain safety switch has tripped twice. Indoor float switch second detection. |
🟡 Book a service call – the drain needs attention before it can run safely. |
| 201 | The outdoor unit can't find the indoor unit it expects. Unit mismatch indoor/outdoor; the second table words it as 'indoor unit is not connected'. |
🟡 Book a service call – this one needs a technician. |
| 202 | The indoor and outdoor units have stopped talking to each other. Indoor/outdoor communication error (1 minute). |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| 203 | The outdoor unit's two circuit boards (main and inverter) have lost communication with each other. Main-inverter micom communication error (1 minute). |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| 221 | The outdoor air temperature sensor isn't reading properly. Outdoor temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| 231 | The outdoor coil (condenser) temperature sensor isn't reading properly. Condenser temperature sensor error. |
🟡 Book a service call – this one needs a technician. |
| 237 | The outdoor coil (condenser) temperature sensor isn't reading properly. COND temperature sensor open/short – listed separately from 231 in the booklet. |
🟡 Book a service call – this one needs a technician. |
| 251 | The compressor discharge temperature sensor isn't reading properly. Inverter compressor discharge temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| 320 | The compressor's overload-protection temperature sensor isn't reading properly. OLP sensor error. |
🟡 Book a service call – this one needs a technician. |
| 403 | The system detected freezing at the outdoor unit and stopped the compressor to protect itself. Outdoor freeze detection while compressor stopped. |
🟡 Check the return-air filters are clean, then book a service if the code stays. |
| 404 | The outdoor unit shut down to protect itself from overloading. Outdoor overload protection while compressor stopped. |
🟡 Check nothing is blocking airflow around the outdoor unit, then book a service if the code stays. |
| 416 | The compressor got too hot and the system shut down to prevent damage. Discharge over-temperature. Can point to low refrigerant. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| 419 | The refrigerant control valve (EEV) failed to open properly. EEV open error. |
🟡 Book a service call – this one needs a technician. |
| 422 | The refrigerant control valve (EEV) failed to close properly. EEV close error (printed 'EVV' in the booklet). |
🟡 Book a service call – this one needs a technician. |
| 425 | The power cabling to the unit is connected incorrectly. Power cable miss-connection error. |
🟡 Book a service call – this needs an electrician or technician, not a DIY fix. |
| 440 | Heating is locked out because the outdoor temperature is too high. Heating-mode ambient lockout. |
🟢 Check the mode setting on the controller. Heating resumes when the outdoor temperature drops back into range – book a service only if it persists in cool weather. |
| 441 | Cooling is locked out because the outdoor temperature is too low. Cooling-mode ambient lockout. |
🟢 Check the mode setting on the controller. Cooling resumes when the outdoor temperature rises back into range – book a service only if it persists in warm weather. |
| 458 | Outdoor fan 1 isn't running properly. Outdoor fan 1 error. |
🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays. |
| 460 | The communication wiring between indoor and outdoor units has been connected to the wrong terminal. Communication wire miss-connection (connected to power terminal). |
🟡 Book a service call – this needs a technician, not a DIY fix. |
| 461 | The compressor is failing to start. Inverter compressor startup error. |
🟡 Book a service call – this one needs a technician. |
| 462 | The unit shut down because it drew too much electrical current. Total current error / PFC over-current error. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| 463 | The compressor got too hot and the unit shut it down to protect it. Booklet prints 'OLP Heat Sink Sensor Error', but no Samsung manual uses that wording and the OLP sensor fault is code 320. Official tables define 463 as the compressor OLP over-temperature / over-current trip – corrected accordingly. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| 464 | The inverter power module tripped on over-current and shut the unit down. Inverter IPM over-current error. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| 465 | The outdoor unit is limiting the compressor because voltage went out of range. Compressor V-limit error; Samsung's CAC manual uses the same wording ('Compressor Vlimit error: E465') and the FJM manual lists 'voltage-limit error of compressor'. The cassette table's 'compressor overload' is the same trip. |
🟡 Book a service call – this one needs a technician. |
| 466 | The power supply to the unit went outside its safe voltage range. DC-link over/low voltage error – the booklet itself suggests restarting after checking power. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| 467 | The outdoor unit can't drive the compressor properly – a compressor rotation fault. Inverter compressor rotation error. |
🟡 Book a service call – this one needs a technician. |
| 468 | A current sensor on the outdoor unit's electronics isn't reading properly. Inverter current sensor error. |
🟡 Book a service call – this one needs a technician. |
| 469 | The voltage sensor on the outdoor unit's inverter board isn't reading properly. Inverter DC-link voltage sensor error. |
🟡 Book a service call – this one needs a technician. |
| 471 | The outdoor unit's control board has a memory fault. Inverter OTP / EEPROM read-write error. |
🟡 Book a service call – this one needs a technician. |
| 472 | The unit can't read the incoming mains power waveform properly. AC zero-crossing signal error. |
🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| 473 | The compressor has seized or locked and won't turn. Compressor lock error. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| 474 | The temperature sensor on the inverter heatsink isn't reading properly. Heat sink sensor error / heatsink temperature over error. |
🟡 Book a service call – this one needs a technician. |
| 475 | Outdoor fan 2 isn't running properly. Outdoor fan 2 error. |
🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays. |
| 484 | The power-correction circuit in the outdoor unit overloaded and shut the unit down. PFC overload error. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| 485 | The sensor that measures incoming electrical current isn't reading properly. Input current sensor error. |
🟡 Book a service call – this one needs a technician. |
| 500 | The inverter electronics overheated and the unit shut down to protect itself. Heat sink over-heat error. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| 554 | The system thinks it has lost refrigerant. Gas leak / full refrigerant leakage error. |
🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician. |
| 556 | The outdoor unit's capacity option hasn't been set up correctly. Outdoor unit capacity setup option error. |
🟡 Book a service call – this one needs a technician. |
| 557 | The indoor units' option codes don't match each other. Option code mismatch among indoor units. |
🟡 Book a service call – this one needs a technician. |
| 601 | The wired controller has lost communication with the indoor unit. Indoor unit to wired remote controller communication error. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| 602 | The two wired controllers (master and slave) have stopped talking to each other. Master-slave controller communication error – usually an option-switch setting. |
🟡 Book a service call – this one needs a technician. |
| 606 | The wired controller is wired to the wrong communication terminal. COM1/COM2 cross-installation error. |
🟡 Book a service call – this one needs a technician. |
| EA | The wired controller's COM2 option switch isn't set correctly. Controller COM2 option setting error (DIP switch). |
🟡 Book a service call – this one needs a technician. |
Ducted range (outdoor unit E-codes)
Where the code shows: Outdoor unit PCB LED display (MAIN and INVERTER boards), reported as E-codes..
Tap your code: E201E202E203E221E231E251E320E403E404E416E440E441E458E475E461E462E463E464E465E466E467E468E471E474E484E500E554E556
| Code | What it means | What to do |
|---|---|---|
| E201 | The outdoor unit can't see the number of indoor units it expects. Indoor/outdoor unit quantity mismatch. |
🟡 Book a service call – this one needs a technician. |
| E202 | The indoor and outdoor units have stopped talking to each other. Indoor-outdoor main PCB communication error. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E203 | The outdoor unit's two circuit boards (main and inverter) have lost communication with each other. Main-inverter communication timeout (1 minute). |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E221 | The outdoor air temperature sensor isn't reading properly. Outdoor temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E231 | The outdoor coil (condenser) temperature sensor isn't reading properly. Condenser temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E251 | The compressor discharge temperature sensor isn't reading properly. Discharge temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E320 | The compressor's overload-protection temperature sensor isn't reading properly. OLP sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E403 | The system detected freezing at the outdoor unit and stopped the compressor to protect itself. Outdoor freeze detection while compressor stopped. |
🟡 Check the return-air filter is clean and nothing is blocking the outdoor unit, then book a service if the code stays. |
| E404 | The outdoor unit shut down to protect itself from overloading. Outdoor overload protection while compressor stopped. |
🟡 Check nothing is blocking airflow around the outdoor unit, then book a service if the code stays. |
| E416 | The compressor got too hot and the system shut down to prevent damage. Compressor discharge over-temperature. Can point to low refrigerant. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E440 | Heating is locked out because the outdoor temperature is above about 30 degrees C. Heating-mode ambient lockout, not a component failure. |
🟢 Check the mode setting. Heating resumes when the outdoor temperature drops back into range – book a service only if it persists in cool weather. |
| E441 | Cooling is locked out because the outdoor temperature is below about -5 degrees C. Cooling-mode ambient lockout, not a component failure. |
🟢 Check the mode setting. Cooling resumes when the outdoor temperature rises back into range – book a service only if it persists in warm weather. |
| E458 | Outdoor fan 1 isn't running properly. Outdoor BLDC fan 1 error. |
🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays. |
| E475 | Outdoor fan 2 isn't running properly. Outdoor BLDC fan 2 error. |
🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays. |
| E461 | The compressor is failing to start. Compressor starting error. |
🟡 Book a service call – this one needs a technician. |
| E462 | The unit shut down because it drew too much electrical current. Primary current trip error. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E463 | The unit tripped on an electrical over-current and shut itself down. Over-current trip / PFC over-current error, remark 'check OLP sensor'. Samsung's own manuals also describe E463 as the compressor's overload protector (OLP) overheating and stopping the compressor – the same protective trip worded two ways. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E464 | The inverter power module tripped on over-current and shut the unit down. IPM (IGBT module) over-current. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E465 | The compressor overloaded and the unit shut down to protect it. Compressor overload error as printed; Samsung manuals elsewhere call the same code the compressor V-limit (voltage-limit) error – same protection. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E466 | The power supply to the unit went outside its safe voltage range. DC-link voltage under/over error – often follows a power glitch or brownout. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E467 | The outdoor unit can't drive the compressor properly – a compressor wiring fault. Compressor wire missing error. |
🟡 Book a service call – this one needs a technician. |
| E468 | A current sensor on the outdoor unit's electronics isn't reading properly. Current sensor error on the inverter board. |
🟡 Book a service call – this one needs a technician. |
| E471 | The outdoor unit's control board has a memory fault. Outdoor EEPROM error. |
🟡 Book a service call – this one needs a technician. |
| E474 | A temperature sensor on the inverter electronics isn't reading properly. IPM (IGBT module) or PFCM temperature sensor error. |
🟡 Book a service call – this one needs a technician. |
| E484 | The power-correction circuit in the outdoor unit overloaded and shut the unit down. PFC overload error. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E500 | The inverter electronics overheated and the unit shut down to protect itself. IPM over-heated. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E554 | The system thinks it has lost refrigerant. Gas leak error. |
🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician. |
| E556 | The indoor and outdoor units aren't a matching capacity pairing. Capacity mismatch between indoor and outdoor unit. |
🟡 Book a service call – this one needs a technician. |
Free Joint Multi (FJM) – indoor unit display codes, MH FVEA / MH FBEA / MH FAEA (AQV heads use the hi-wall split LED patterns)
Where the code shows: Indoor unit display, shown as a split two-part code (e.g. 'E1 01' = E101)..
| Code | What it means | What to do |
|---|---|---|
| E101 | The indoor unit has stopped receiving data from the outdoor unit. Communication error – unable to receive data. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E102 | The outdoor unit can't communicate with this indoor unit. Communication error – outdoor cannot communicate; may involve another indoor unit or the indoor PCB. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E121 | The indoor unit's room temperature sensor isn't reading properly. Room temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E122 | The indoor coil inlet temperature sensor isn't reading properly. Heat exchanger in sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E123 | The indoor coil outlet temperature sensor isn't reading properly. Heat exchanger out sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E128 | The indoor coil inlet sensor has come loose from its mounting. Heat exchanger in sensor detached. |
🟡 Book a service call – this one needs a technician. |
| E129 | The indoor coil outlet sensor has come loose from its mounting. Heat exchanger out sensor detached. |
🟡 Book a service call – this one needs a technician. |
| E130 | Both indoor coil sensors have come loose from their mountings. Heat exchanger in and out sensors detached. |
🟡 Book a service call – this one needs a technician. |
| E153 | The condensate drain system has flagged high water – the drain safety switch has tripped twice. Indoor float switch second detection. |
🟡 Book a service call – the drain needs attention before it can run safely. |
| E154 | The indoor fan motor isn't running properly. Indoor fan motor malfunction. |
🟡 Book a service call – this one needs a technician. |
| E161 | Two or more indoor units are asking for opposite modes at once (some cooling, some heating). Simultaneous cool/heat operation error – a multi-head system can only run one mode at a time. |
🟢 Set every indoor unit to the same mode (all cooling or all heating), then try again. If the code stays, book a service. |
| E162 | The indoor unit's control board has a memory fault. Indoor EEPROM error. |
🟡 Book a service call – this one needs a technician. |
| E163 | The indoor unit's model option code hasn't been set correctly. Option code setting error. |
🟡 Book a service call – this one needs a technician. |
| E185 | The cabling between indoor and outdoor units is connected incorrectly. Cable miss-wiring between indoor and outdoor unit. |
🟡 Book a service call – this needs a technician, not a DIY fix. |
| E186 | The indoor unit's MPI (plasma/purifier module) has a fault. MPI error malfunction. |
🟡 Book a service call – this one needs a technician. |
| E201 | The outdoor unit can't see the number of indoor units it expects. Number of indoor units mismatched – check cabling and outdoor switch settings (technician task). |
🟡 Book a service call – this one needs a technician. |
| E251 | The compressor discharge temperature sensor isn't reading properly. Compressor discharge sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E259 | The outdoor unit has a fault – its own display shows the specific code. Outdoor unit error, see outdoor unit error code. |
🟡 Book a service call – this one needs a technician. |
Free Joint Multi (FJM) – outdoor unit PCB display codes
Where the code shows: Outdoor unit PCB display, shown as a split two-part code (e.g. 'E4 61' = E461)..
Tap your code: E101E102E121E122E123E128E129E154E161E162E163E190E199E201E202E203E221E237E246E251E261E320E330E331E332E333E334E335E336E337E338E339E401E404E416E419E422E440E441E458E460E461E462E463E464E465E466E467E468E469E471E472
| Code | What it means | What to do |
|---|---|---|
| E101 | The indoor unit has stopped receiving data from the outdoor unit. Communication error – indoor unable to receive data. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E102 | The outdoor unit is receiving bad data from an indoor unit. Outdoor communication error – abnormal data over 60 packets. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E121 | An indoor unit's room temperature sensor isn't reading properly. Indoor room temperature sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E122 | An indoor coil inlet temperature sensor isn't reading properly. Indoor heat exchanger in sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E123 | An indoor coil outlet temperature sensor isn't reading properly. Indoor heat exchanger out sensor open/short. |
🟡 Book a service call – this one needs a technician. |
| E128 | An indoor coil inlet sensor has come loose from its mounting. Evaporator pipe-in sensor self-diagnosis error. |
🟡 Book a service call – this one needs a technician. |
| E129 | An indoor coil outlet sensor has come loose from its mounting. Evaporator pipe-out sensor self-diagnosis error. |
🟡 Book a service call – this one needs a technician. |
| E154 | An indoor fan motor isn't running properly. Indoor unit fan error. |
🟡 Book a service call – this one needs a technician. |
| E161 | Two or more indoor units are asking for opposite modes at once (some cooling, some heating). Simultaneous cool/heat operation error. |
🟢 Set every indoor unit to the same mode (all cooling or all heating), then try again. If the code stays, book a service. |
| E162 | An indoor unit's control board has a memory fault. Indoor unit EEPROM error. |
🟡 Book a service call – this one needs a technician. |
| E163 | An indoor unit's model option code hasn't been set correctly. Indoor unit EEPROM option error. |
🟡 Book a service call – this one needs a technician. |
| E190 | The system's pipe-check (pairing) routine failed. Failure of pipe check operation – a commissioning issue. |
🟡 Book a service call – this one needs a technician. |
| E199 | The system was started without completing its pipe-check (pairing) routine. No pipe check operation done after auto-addressing – a commissioning issue. |
🟡 Book a service call – this one needs a technician. |
| E201 | The outdoor unit can't see the number of indoor units it expects. Number of indoor units mismatched. |
🟡 Book a service call – this one needs a technician. |
| E202 | The indoor and outdoor units have stopped talking to each other. Outdoor-indoor communication error. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E203 | The outdoor unit's two circuit boards (main and sub) have lost communication with each other. Outdoor main PCB to sub PCB communication error. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E221 | The outdoor air temperature sensor isn't reading properly. Outside (ambient) temperature sensor short/open. The booklet misprints this as 'E3 21'; official FJM manuals list E221, and the printed voltage thresholds match the E221 row exactly. |
🟡 Book a service call – this one needs a technician. |
| E237 | The outdoor coil (condenser) temperature sensor isn't reading properly. Condenser temperature sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E246 | The outdoor coil outlet temperature sensor isn't reading properly. Condenser-out sensor short/open, self-diagnosis. |
🟡 Book a service call – this one needs a technician. |
| E251 | The compressor discharge temperature sensor isn't reading properly. Compressor discharge temperature sensor error. |
🟡 Book a service call – this one needs a technician. |
| E261 | The compressor discharge sensor has come loose from its mounting. Compressor discharge sensor detached, self-diagnosis. |
🟡 Book a service call – this one needs a technician. |
| E320 | The compressor's overload-protection temperature sensor isn't reading properly. Compressor OLP sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E330 | The coil inlet sensor for circuit 1 isn't reading properly. EvaIn1 sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E331 | The coil inlet sensor for circuit 2 isn't reading properly. EvaIn2 sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E332 | The coil inlet sensor for circuit 3 isn't reading properly. EvaIn3 sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E333 | The coil inlet sensor for circuit 4 isn't reading properly. EvaIn4 sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E334 | The coil inlet sensor for circuit 5 isn't reading properly. EvaIn5 sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E335 | The coil outlet sensor for circuit 1 isn't reading properly. EvaOut1 sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E336 | The coil outlet sensor for circuit 2 isn't reading properly. EvaOut2 sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E337 | The coil outlet sensor for circuit 3 isn't reading properly. EvaOut3 sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E338 | The coil outlet sensor for circuit 4 isn't reading properly. EvaOut4 sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E339 | The coil outlet sensor for circuit 5 isn't reading properly. EvaOut5 sensor short/open. |
🟡 Book a service call – this one needs a technician. |
| E401 | The system detected freezing and stopped the compressor to protect itself. Outdoor unit freezing protection – booklet lists dirty indoor filters and refrigerant charge among the causes. |
🟡 Check the indoor units' filters are clean, then book a service if the code stays. |
| E404 | The outdoor unit shut down to protect itself from overloading. Outdoor overload safety control – booklet points at pipe length and refrigerant charge. |
🟡 Check nothing is blocking airflow around the outdoor unit, then book a service if the code stays. |
| E416 | The compressor got too hot and the system shut down to prevent damage. High discharge temperature safety control – booklet points at refrigerant leakage/charge. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E419 | A refrigerant control valve (EEV) fault was detected on indoor circuits that are switched off. Outdoor unit EEV open, detected on stopped indoor units (self diagnosis). Booklet printed 'E4 29'; the FJM Plus service manual lists the self-diagnosis EEV codes as 419 (stopped) and 422 (operating), and the booklet's own controller table has 419 = EEV open. E429 in Samsung literature is a compression-rate error, not EEV – corrected. |
🟡 Book a service call – this one needs a technician. |
| E422 | A refrigerant control valve (EEV) fault was detected on indoor circuits that are running. Outdoor unit EEV open, detected on operating indoor units (self diagnosis), pairing with E419 for stopped units. Samsung's E422 service guide (Jan 2025) also defines E422 as an EEV open error on FJM/RAC/CAC. Note: the current AJ-series FJM generation reuses E422 for high-pressure blockage control. |
🟡 Book a service call – this one needs a technician. |
| E440 | Heating is locked out because the outdoor temperature is above about 30 degrees C. Heating-mode ambient lockout, not a component failure. |
🟢 Check the mode setting. Heating resumes when the outdoor temperature drops back into range – book a service only if it persists in cool weather. |
| E441 | Cooling is locked out because the outdoor temperature is below about -10 degrees C. Cooling-mode ambient lockout, not a component failure. |
🟢 Check the mode setting. Cooling resumes when the outdoor temperature rises back into range – book a service only if it persists in warm weather. |
| E458 | The outdoor fan isn't running properly. Outdoor fan error. |
🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays. |
| E460 | The communication cable between indoor and outdoor units is connected to the wrong terminal. Communication cable mismatched between indoor and outdoor unit. |
🟡 Book a service call – this needs a technician, not a DIY fix. |
| E461 | The compressor failed to start after several attempts. Inverter compressor starting failure (5 attempts). |
🟡 Book a service call – this one needs a technician. |
| E462 | The unit shut the compressor down because it was drawing too much current. Compressor trip by input current control (PFC over-current). |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E463 | The compressor got too hot and the unit shut it down to protect it. Compressor trip by OLP temperature control. Official FJM manual AC-00261E: 'compressor operation stop due to OLP temperature control'. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E464 | The unit shut down because it drew too much electrical current. Over-current error. |
🔴 Turn the system off at the isolator and call us – don't keep running it. |
| E465 | The outdoor unit is limiting the compressor because voltage went out of range. Compressor V-limit (voltage-limit) error per official FJM manual AC-00261E. Samsung's CAC tables label the same code 'compressor overload' – same protective trip. |
🟡 Book a service call – this one needs a technician. |
| E466 | The power supply to the unit went outside its safe voltage range. DC-link voltage error (under 150V / over 410V) – often follows a power glitch or brownout. |
🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
| E467 | The compressor isn't rotating the way the controller expects. Compressor rotation error. |
🟡 Book a service call – this one needs a technician. |
| E468 | A current sensor on the outdoor unit's electronics isn't reading properly. Current sensor error. |
🟡 Book a service call – this one needs a technician. |
| E469 | The voltage sensor on the outdoor unit's inverter board isn't reading properly. DC-link voltage sensor error. |
🟡 Book a service call – this one needs a technician. |
| E471 | The outdoor unit's control board has a memory fault. OTP error. |
🟡 Book a service call – this one needs a technician. |
| E472 | The unit can't read the incoming mains power waveform properly. Inverter micom zero-crossing error. |
🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service. |
Code still showing after a reset? Mention the code and your system type when you book and our office can line up the right technician and likely parts before we arrive.
Book a service or call (02) 4760 0100 (24-hour line, Penrith & Blue Mountains).
Codes vary between models and generations, and manufacturers revise them. This guide is compiled from official service documentation and checked by Ample Air, but it is general information, not a diagnosis. Refrigerant and electrical work must be carried out by licensed technicians. Ample Air, ARC licences AU12976 & AU15788. Last verified August 2026.