What does your LG fault code mean?

Pick the code showing on your remote, wall controller or indoor unit and see what it means, what commonly causes it, and what is safe to check yourself. This page covers 56 LG fault codes for units sold in Australia, compiled from official Australian manufacturer and distributor documentation, the same references our own technicians carry.

Heads up: LG uses the same code with different meanings on different product ranges, so check the model range shown next to the code.

Every LG fault code at a glance

Some models show faults as a flashing-light pattern instead of a code; documented lamp patterns are listed alongside their codes.

Code What it means Severity
13 (Older wall splits (RAC models) that show two digit or letter codes)
also shown as CD
The power converter (reactor) circuit in the outdoor unit’s inverter has reported a fault, the same protection family as CH27. Fault – service needed
14 (Older wall splits (RAC models) that show two digit or letter codes)
also shown as CE
The outdoor unit has measured abnormal current in one of the compressor’s motor windings. Fault – service needed
CH00 (All system types)
also shown as CH 00, 00
A general fault indication meaning the unit has detected a problem and needs inspection. Minor fault
CH01 (Splits, ducted, multi-head and cassettes)
also shown as 01, C1, 1 blink on indoor LED
The indoor unit’s return air temperature sensor has failed or lost connection. Fault – service needed
CH02 (Splits, ducted, multi-head and cassettes)
also shown as 02, C2, 2 blinks on indoor LED
The indoor unit’s inlet pipe temperature sensor (or on some models the outdoor sensor assembly) has failed or lost connection. Fault – service needed
CH03 (Systems with a wired wall controller (ducted, cassettes, some multi-head))
also shown as 03
The wired remote controller has lost communication with the indoor unit. Fault – service needed
CH04 (All system types; shows as FL on some portable and window models)
also shown as 04, C4, FL
The unit has detected a drainage problem, meaning condensate water is not draining away properly. On some older wall splits CH04 can instead indicate a heat sink sensor fault. Minor fault
CH05 (All inverter system types; on some models the display shows EO while the kW Manager energy feature is running, which is normal operation and not a fault)
also shown as 05, C5, E0, 5 blinks on indoor LED
The indoor unit and outdoor unit have stopped communicating with each other. Fault – service needed
CH06 (Splits, ducted, multi-head and cassettes; on some older wall splits a displayed 6 or C6 means compressor over current instead (see CH21))
also shown as 06, 6 blinks on indoor LED
The indoor unit’s coil (outlet pipe) temperature sensor has failed or lost connection. Fault – service needed
CH07 (Multi-head systems (also 2-in-1 combos); on single splits the same number (shown as C7 on some older displays) means compressor over current)
also shown as 07, C7
The indoor units on a multi-head system are set to conflicting modes, for example one head cooling while another is heating. Minor fault
CH08 (Wall-mounted splits (residential models))
also shown as 08, C8
The indoor unit’s fan motor has locked up and cannot spin. Fault – service needed
CH09 (Varies by series: indoor unit memory error on many models, outdoor fan fault on some splits)
also shown as 09, C9, 9 blinks on indoor LED
On most models this is an indoor unit control board memory (EEPROM) error; on some splits it indicates an outdoor fan motor problem. Fault – service needed
CH10 (All system types; on some older wall splits (shown as 10 or CA) it means a compressor discharge sensor fault)
also shown as 10, E6, CA
The indoor unit’s fan has locked up or the fan motor has failed. On some older wall splits CH10 can instead indicate a compressor discharge pipe temperature sensor fault. Fault – service needed
CH12 (Splits, ducted, multi-head and cassettes)
also shown as 12, CC
The indoor unit’s middle pipe temperature sensor has failed or lost connection. On some older wall splits 12 (shown as CC on the display) instead means the control board memory has failed its check. Fault – service needed
CH21 (All inverter system types (outdoor unit fault); shows as C6 on some older wall split displays)
also shown as 21, C6
The outdoor unit detected a sudden spike in compressor voltage or current (DC peak or IPM fault) and shut down to protect itself. Fault – service needed
CH22 (All inverter system types (outdoor unit fault))
also shown as 22
The incoming electrical current to the outdoor unit is too high (CT2 over current). Fault – service needed
CH23 (All inverter system types (outdoor unit fault))
also shown as 23
The DC voltage inside the outdoor unit’s inverter is too low. Fault – service needed
CH24 (Splits and multi-head systems)
also shown as 24
The refrigerant pressure has gone outside safe limits (too high or too low) and the system has tripped to protect itself. Urgent – turn it off
CH25 (All inverter system types (outdoor unit fault))
also shown as 25
The power supply voltage to the outdoor unit is too low or too high. Fault – service needed
CH26 (All inverter system types (outdoor unit fault))
also shown as 26
The inverter compressor has seized or is failing to rotate. Fault – service needed
CH27 (All inverter system types (outdoor unit fault))
also shown as 27
The current in the outdoor unit’s power converter circuit is too high (PSC or reactor fault). Fault – service needed
CH28 (All inverter system types (outdoor unit fault))
also shown as 28
The DC voltage inside the outdoor unit’s inverter is too high. Fault – service needed
CH29 (All inverter system types (outdoor unit fault))
also shown as 29
The inverter compressor is drawing too much current. Fault – service needed
CH31 (All inverter system types (outdoor unit fault))
also shown as 31
The current measured by the outdoor unit’s current sensor is too low. Fault – service needed
CH32 (All inverter system types (outdoor unit fault))
also shown as 32
The compressor’s discharge pipe temperature is too high and the system has shut down to protect itself. Urgent – turn it off
CH34 (Systems with a high pressure sensor (larger splits, ducted); also shown as an overheat variant on some models)
also shown as 34
The refrigerant pressure has risen too high and the system has shut down to protect itself. Urgent – turn it off
CH35 (Systems with a low pressure sensor (larger splits, ducted))
also shown as 35
The refrigerant pressure has dropped too low and the system has shut down to protect itself. Urgent – turn it off
CH38 (All inverter system types; shows as F4 on some models)
also shown as 38, F4
The system has detected it is low on refrigerant gas and has stopped to protect itself. Urgent – turn it off
CH40 (All inverter system types (outdoor unit fault))
also shown as 40
The outdoor unit’s current sensor (CT sensor) has failed or lost connection. Fault – service needed
CH41 (All inverter system types (outdoor unit fault))
also shown as 41
The inverter compressor’s discharge pipe temperature sensor has failed or lost connection. Fault – service needed
CH42 (Systems with a low pressure sensor (larger splits, ducted))
also shown as 42
The refrigerant low pressure sensor has failed or is giving a faulty reading. Fault – service needed
CH43 (Systems with a high pressure sensor (larger splits, ducted))
also shown as 43
The refrigerant high pressure sensor has failed or is giving a faulty reading. Fault – service needed
CH44 (All system types (outdoor unit fault))
also shown as 44
The outdoor unit’s air temperature sensor has failed or lost connection. Fault – service needed
CH45 (All system types (outdoor unit fault))
also shown as 45
The outdoor unit’s condenser coil (middle) temperature sensor has failed or lost connection. Fault – service needed
CH46 (All system types (outdoor unit fault))
also shown as 46
The outdoor unit’s suction line temperature sensor has failed or lost connection. Fault – service needed
CH47 (All system types (outdoor unit fault))
also shown as 47
The compressor discharge temperature sensor has failed or lost connection. Fault – service needed
CH48 (Splits, ducted and multi-head (outdoor unit fault))
also shown as 48
The outdoor unit’s coil outlet (liquid line) sensor has failed, or both the discharge and air sensors have come unplugged. Fault – service needed
CH49 (All system types (outdoor unit fault))
also shown as 49
The power supply to the outdoor unit is faulty or outside the acceptable voltage range. Fault – service needed
CH51 (Multi-head systems)
also shown as 51
The connected indoor units exceed the capacity the outdoor unit can support (unit mismatch). Fault – service needed
CH52 (All inverter system types (outdoor unit fault))
also shown as 52
The two circuit boards inside the outdoor unit (inverter board and main board) have stopped communicating. Fault – service needed
CH53 (All inverter system types)
also shown as 53
The outdoor unit has lost communication with the indoor unit. Fault – service needed
CH54 (Three phase systems (larger ducted); can appear after a power outage or electrical work)
also shown as 54
The outdoor unit has detected a reverse or missing phase in its three phase power supply. Fault – service needed
CH57 (All inverter system types (outdoor unit fault))
also shown as 57
The outdoor unit’s main board and inverter board have stopped communicating with each other. Fault – service needed
CH60 (All system types (outdoor unit fault))
also shown as 60
The outdoor unit’s control board memory (EEPROM) has failed its check. Fault – service needed
CH61 (All system types; shows as P4, P6, P7 or P8 on some models)
also shown as 61, P4, P6, P7, P8
The outdoor unit’s coil has become too hot (in cooling) or the indoor unit has overheated (in heating), usually from poor airflow. Minor fault
CH62 (All inverter system types (outdoor unit fault))
also shown as 62
The heat sink on the outdoor unit’s inverter board has become too hot. Fault – service needed
CH63 (Splits, ducted and multi-head (outdoor unit fault))
also shown as 63
The outdoor unit’s condenser coil pipe temperature reading is abnormally low. Fault – service needed
CH65 (All inverter system types (outdoor unit fault))
also shown as 65
The temperature sensor on the outdoor unit’s inverter heat sink has failed or lost connection. Fault – service needed
CH66 (Inverter models (splits, ducted, multi-head))
also shown as 66
There is a problem with the communication line or the pipe connection between the indoor and outdoor units. Fault – service needed
CH67 (All system types; shows as EF on some models)
also shown as 67, EF
The outdoor unit’s fan motor has seized or its rotation cannot be detected. Fault – service needed
CH90 (All inverter system types, usually during the installation test run)
also shown as 90, F4
A protection error shown during the test run to stop the unit being damaged, most often pointing to a piping or refrigerant issue. Fault – service needed
CH91 (All inverter system types, usually during the installation test run)
also shown as 91
A protection error shown during the test run to stop the unit being damaged, most often pointing to a piping or refrigerant issue. Fault – service needed
CH93 (All inverter system types; on models made after 2021 it can mean the outdoor unit has no power)
also shown as 93
The indoor and outdoor units cannot communicate, typically during the test run or because the outdoor unit is not receiving power. Fault – service needed
CL (Wall-mounted splits and portables with remote control) The child lock feature is switched on; this is not a fault. Normal operation
HL (Ducted, cassette and other systems with a condensate pump) The condensate float switch has risen, meaning water is not draining away and the safety switch has stopped the unit. Minor fault
Po (Wall-mounted splits)
also shown as PO
Jet Cool (power cool) mode is running; this is not a fault. Normal operation

Codes that mean switch the system off

If your LG unit shows CH24, CH32, CH34, CH35, CH38, turn the system off at the isolator and leave it off. These faults involve the compressor, refrigerant or electrical protection, and running the unit can cause further damage.

The most serious LG fault codes explained

What does LG fault code CH24 mean? (Splits and multi-head systems)

The refrigerant pressure has gone outside safe limits (too high or too low) and the system has tripped to protect itself.

Likely causes:

  • Refrigerant leak (low pressure)
  • Blocked or restricted airflow over the coils (high pressure)
  • Refrigerant system blockage
  • Pressure switch fault

Safe checks before you call:

  • Clear leaves, boxes or plants from around the outdoor unit
  • Clean the indoor unit return air filters
  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH32 mean? (All inverter system types (outdoor unit fault))

The compressor’s discharge pipe temperature is too high and the system has shut down to protect itself.

Likely causes:

  • Low refrigerant charge
  • Blocked airflow over the outdoor coil
  • Refrigerant system restriction

Safe checks before you call:

  • Clear leaves, boxes or plants from around the outdoor unit
  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH34 mean? (Systems with a high pressure sensor (larger splits, ducted); also shown as an overheat variant on some models)

The refrigerant pressure has risen too high and the system has shut down to protect itself.

Likely causes:

  • Blocked or restricted airflow over the coils
  • Dirty outdoor coil or clogged filters
  • Air or contamination in the refrigerant circuit
  • Refrigerant overcharge

Safe checks before you call:

  • Clear leaves, boxes or plants from around the outdoor unit
  • Clean the indoor unit return air filters
  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH35 mean? (Systems with a low pressure sensor (larger splits, ducted))

The refrigerant pressure has dropped too low and the system has shut down to protect itself.

Likely causes:

  • Refrigerant leak
  • Service valve not fully open after installation
  • Refrigerant system restriction

Safe checks before you call:

  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH38 mean? (All inverter system types; shows as F4 on some models)

The system has detected it is low on refrigerant gas and has stopped to protect itself.

Likely causes:

  • Refrigerant leak
  • Poor pipe connection from installation or relocation
  • Temporary electrical glitch

Safe checks before you call:

  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH01 mean? (Splits, ducted, multi-head and cassettes)

The indoor unit’s return air temperature sensor has failed or lost connection.

Likely causes:

  • Sensor has failed (open or short circuit)
  • Sensor plug loose on the indoor circuit board
  • Indoor circuit board fault

Safe checks before you call:

  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH02 mean? (Splits, ducted, multi-head and cassettes)

The indoor unit’s inlet pipe temperature sensor (or on some models the outdoor sensor assembly) has failed or lost connection.

Likely causes:

  • Sensor has failed (open or short circuit)
  • Sensor plug loose on the circuit board
  • Circuit board fault

Safe checks before you call:

  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH03 mean? (Systems with a wired wall controller (ducted, cassettes, some multi-head))

The wired remote controller has lost communication with the indoor unit.

Likely causes:

  • Controller cable damage or loose connection
  • Wrong controller group setting after installation or repair
  • Controller or indoor circuit board fault

Safe checks before you call:

  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH05 mean? (All inverter system types; on some models the display shows EO while the kW Manager energy feature is running, which is normal operation and not a fault)

The indoor unit and outdoor unit have stopped communicating with each other.

Likely causes:

  • Interconnecting cable fault or loose terminal
  • No power to the outdoor unit
  • Unstable power supply causing a temporary dropout
  • Indoor or outdoor circuit board fault

Safe checks before you call:

  • Check the outdoor unit isolator switch is on
  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH06 mean? (Splits, ducted, multi-head and cassettes; on some older wall splits a displayed 6 or C6 means compressor over current instead (see CH21))

The indoor unit’s coil (outlet pipe) temperature sensor has failed or lost connection.

Likely causes:

  • Sensor has failed (open or short circuit)
  • Sensor plug loose on the indoor circuit board
  • Indoor circuit board fault

Safe checks before you call:

  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH08 mean? (Wall-mounted splits (residential models))

The indoor unit’s fan motor has locked up and cannot spin.

Likely causes:

  • Fan motor failure
  • Fan motor plug loose on the circuit board
  • Something jamming the indoor fan
  • Indoor circuit board fault

Safe checks before you call:

  • Clean the indoor unit return air filters
  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

What does LG fault code CH09 mean? (Varies by series: indoor unit memory error on many models, outdoor fan fault on some splits)

On most models this is an indoor unit control board memory (EEPROM) error; on some splits it indicates an outdoor fan motor problem.

Likely causes:

  • Indoor circuit board memory fault
  • Outdoor fan motor failure on some split models
  • Circuit board needs replacement or reprogramming

Safe checks before you call:

  • Turn the system off at the isolator or breaker, wait 5 minutes, then turn it back on

Fault confirmed? Here is what to do next

A fault code is the starting point, not the fix. Start here:

Call us on 08 8296 7888 or book online and we will call or text you back ASAP.

Sources for this page

Every LG code above is checked against these Australian documents. Open them yourself to verify anything on this page:

LG fault code FAQs

Where do I find the fault code on a LG air conditioner?

Check the remote or wall controller display first. Some models flash the indoor unit’s lamps in a pattern instead; the table above lists documented lamp patterns alongside their codes. If nothing is showing, the code may only appear while the fault is active.

Can I clear a LG fault code myself?

You can reset the system by turning it off at the isolator or breaker for five minutes. If the code stays gone, it was a one-off. If it returns, the fault is real and needs a licensed technician, and repeated resets can cause further damage on compressor or refrigerant faults.

Does a LG fault code mean I need a new air conditioner?

Usually not. Most codes point to repairable faults like sensors, fan motors or drainage. Our fault find gives you an honest verdict either way, and the fee is credited if you repair with us.

Are these LG fault codes correct for Australian models?

Yes. Every code on this page was checked against Australian documentation (lg.com/au, arma.org.au, valleyairconditioning.com.au), not overseas lists, because the same code can mean different things in different markets. Meanings still vary between model series, so treat this page as reference and cross-check your unit’s manual.

Written by Oliver Hastings, T&K Airpower. Last updated 01/08/2026. Compiled from Australian sources including lg.com/au, arma.org.au, valleyairconditioning.com.au, aircaresolutionsnsw.com.au, so you can check every code against the official documentation. Fault code meanings vary between model series and controllers, so treat this page as reference only and never remove panels or work on the refrigeration or electrical parts of the system yourself.

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