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Aircon showing an error code? Look it up here.

Select your brand and fault code to get guidance on what the code means, what's safe to check, and when to contact a technician.

How to use this tool

Use this lookup to understand what a code usually points to and what is safe to check first. This tool gives general guidance only — it cannot confirm which part has failed. If you need help now, contact us now.

Safety warning

Stop using the unit and contact a technician if the breaker trips repeatedly, you smell burning, see sparks, hear loud electrical buzzing, or water is leaking from places it normally should not.

Aircon Error Code Lookup

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Browse the full code index

Search all supported error codes in one place, then narrow by brand tags. Each result shows the same guidance summary used in the lookup tool.

Daikin · A1

Indoor PCB fault

Main control board inside the indoor unit has failed, often from a power surge, age, or moisture.

Daikin · A3

Drain float switch fault

The drain pan is full or the condensate pipe is blocked, triggering the float switch.

Daikin · A5

Indoor coil high-temperature protection

Restricted airflow or low refrigerant caused the indoor coil to overheat or ice up.

Daikin · A6

Indoor fan motor fault

The indoor blower motor has seized, lost a bearing, or the blower wheel is obstructed.

Daikin · A7

Swing flap motor fault

The louver motor has failed or the flap is physically jammed.

Daikin · A9

Indoor electronic expansion valve fault

The electronic expansion valve coil or valve body has failed.

Daikin · C4

Indoor heat exchanger thermistor fault

The temperature sensor on the indoor coil is open-circuit or short-circuit, often after water ingress.

Daikin · C9

Indoor intake air temperature sensor fault

The air intake thermistor has failed or become disconnected.

LG · CH01

Indoor room temperature sensor fault

The indoor air thermistor has failed, often after moisture exposure.

LG · CH02

Indoor coil temperature sensor fault

The indoor coil thermistor has failed.

LG · CH03

Outdoor temperature sensor fault

The outdoor ambient thermistor is open or short-circuit.

LG · CH04

Outdoor discharge temperature sensor fault

The high-side pipe sensor at the compressor outlet has failed.

LG · CH05

Outdoor coil temperature sensor fault

The outdoor heat exchanger thermistor has failed.

LG · CH09

Indoor fan motor error

The indoor blower motor has failed or a speed feedback error is occurring.

LG · CH10

Indoor PCB fault

The indoor control board has failed.

LG · CH11

Indoor-outdoor communication error

The signal cable between units is damaged, loose, or incorrectly connected — sometimes caused by pest damage.

LG · CH12

Outdoor PCB fault

The outdoor main control board has failed.

LG · CH13

Outdoor fan motor error

The outdoor fan motor has failed or the fan blade is jammed.

LG · CH21

High-pressure protection

Refrigerant overcharge, dirty condenser coil, or outdoor fan failure caused pressure to spike.

LG · CH22

Low-pressure protection

Refrigerant is low due to a leak, or the air filter is heavily blocked.

LG · CH23

Anti-freeze protection triggered

The indoor coil has iced up from restricted airflow or low refrigerant.

LG · CH24

Discharge temperature protection

Compressor outlet temperature is too high — usually from low refrigerant or a degrading compressor.

LG · CH29

Compressor overload protection

The compressor is drawing excessive current due to mechanical wear or refrigerant imbalance.

LG · CH32

Inverter PCB fault

The inverter power module has failed, commonly after a lightning strike or power surge.

LG · CH36

Compressor startup failure

The compressor cannot start — mechanical lock, low voltage, or a failed capacitor.

LG · CH38

Outdoor expansion valve fault

The outdoor EEV coil or valve body has failed.

LG · CH44

Drain full / float switch triggered

The drain pan is full or the condensate pipe is blocked or kinked.

LG · CH45

Indoor water leak protection

Water has accumulated in the drain pan, triggering the float switch.

LG · CH60

Indoor fan motor speed feedback error

The indoor fan motor hall sensor or motor winding has failed.

LG · CH61

Outdoor fan motor speed feedback error

The outdoor fan motor hall sensor or winding has failed.

LG · CH68

Compressor speed deviation

The compressor is not reaching target RPM — indicating mechanical wear or an inverter issue.

Mitsubishi Electric · E0

Remote controller fault

The remote controller has an internal fault or has lost communication with the indoor unit.

Daikin · E1

Outdoor PCB fault

The outdoor unit's main control board has failed.

Mitsubishi Electric · E1

Indoor PCB fault

The indoor unit's main control board has failed.

Daikin · E3

High-pressure protection

Refrigerant overcharge, dirty condenser coil, or outdoor fan failure caused pressure to spike.

Mitsubishi Electric · E3

Indoor fan motor lock

The indoor blower motor has seized or the blower wheel is jammed by debris.

Daikin · E4

Low-pressure protection

Refrigerant is low due to a leak, or airflow to the outdoor unit is severely restricted.

Mitsubishi Electric · E4

Anti-freeze protection triggered

The indoor coil has iced up due to a dirty filter or insufficient airflow.

Daikin · E5

Outdoor inverter overload protection

The compressor is drawing excessive current due to age, wear, or a refrigerant imbalance.

Daikin · E6

Compressor startup fault

The compressor cannot start — typically a seized compressor, failed capacitor, or low supply voltage.

Mitsubishi Electric · E6

Compressor lock / overload

The compressor has mechanically failed, seized, or is receiving insufficient supply voltage.

Daikin · E7

Outdoor fan motor fault

The outdoor fan motor has failed or is blocked by debris.

Mitsubishi Electric · E7

Outdoor fan motor lock

The outdoor fan motor has failed or the fan blade is obstructed.

Daikin · E8

Inverter overcurrent protection

A power supply issue or compressor fault is causing the inverter to draw excess current.

Daikin · E9

Outdoor electronic expansion valve fault

The outdoor EEV coil or valve body has failed.

Mitsubishi Electric · E9

Electronic expansion valve fault

The EEV coil or valve body has failed, or a refrigerant issue is causing abnormal valve behaviour.

Mitsubishi Electric · F1

Indoor return air thermistor fault

The return air temperature sensor wire is broken or the connector has pulled loose.

Mitsubishi Electric · F2

Indoor liquid pipe thermistor fault

The temperature sensor on the indoor coil liquid pipe has failed.

Daikin · F3

Discharge pipe temperature too high

Refrigerant is undercharged or the condenser coil is blocked, causing compressor discharge temperature to spike.

Mitsubishi Electric · F3

Outdoor temperature thermistor fault

The outdoor ambient temperature sensor is open or short-circuit.

Daikin · H6

Indoor DC fan motor position error

The hall sensor in the indoor fan motor is faulty or the motor winding has failed.

Daikin · J3

Discharge pipe temperature sensor fault

The thermistor at the compressor outlet has failed.

Daikin · L1

Inverter PCB fault

The inverter module has been damaged, often from a power surge or sustained compressor overload.

Daikin · L4

Inverter heatsink overtemperature

Ventilation around the inverter heatsink is blocked, or the heatsink cooling fan has failed.

Daikin · LC

Indoor-outdoor communication error

Signal wiring between the indoor and outdoor units is loose, damaged, or cut — sometimes by pests.

Mitsubishi Electric · P1

Indoor room temperature thermistor fault

The room temperature sensor has failed, often after moisture ingress.

Mitsubishi Electric · P4

Drain float switch protection

The drain pan is full or the condensate pipe is blocked.

Mitsubishi Electric · P6

Freeze protection triggered

The evaporator coil has iced up due to restricted airflow or low refrigerant.

Mitsubishi Electric · P9

Indoor fan motor feedback error

The fan motor speed is not matching the controller's command — motor or PCB fault.

Mitsubishi Electric · PA

Compressor overload relay tripped

The compressor thermal protection has tripped due to overheating or overload.

Daikin · U0

Refrigerant shortage detected

Refrigerant level is critically low, indicating a leak in the system.

Daikin · U2

Power supply voltage abnormality

Mains voltage is outside the acceptable operating range.

Mitsubishi Electric · U2

Power supply low voltage

Mains supply is dropping below the unit's operating range.

Daikin · U4

Controller communication error

The wired remote controller cable is loose or the controller PCB has failed.

Mitsubishi Electric · U4

Indoor-outdoor communication failure

The signal cable between indoor and outdoor units is damaged or the PCB has failed.

Mitsubishi Electric · U6

Compressor overcurrent / IPM fault

The inverter power module has been damaged, often from a power surge or sustained compressor fault.

Mitsubishi Electric · Ud

Indoor-outdoor communication error

The inter-unit wiring is loose, broken, or affected by pests.

Common questions

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