Model reference

LG ARNU18GTEA0

Air Conditioner

1 document152 error codes5 service modes

Available documentation

Service Manual

Air Conditioner Service Manual338 pg
Covers this model

MyPros+ Max

Diagnose your LG ARNU18GTEA0.

Step-by-step diagnostics from the service manual
Test values, resistance specs, and wiring references
Verified part numbers when replacement is needed

Start diagnosing

$29/month · Cancel anytime · Or $9.95 3-day pass · Plus applicable tax

Error codes (152)

CodeMeaning

01Indoor unit air temperature sensor is open or short circuit.02Indoor unit inlet pipe temperature sensor is open or short circuit.03Transmission error between wired remote controller and indoor unit PCB.04Malfunction of drain pump (float switch open due to rising condensate water…05Transmission error between outdoor unit and indoor unit (no signal received).06Indoor unit outlet pipe temperature sensor is open or short circuit.07Operation mode conflict between indoor units (different modes running…09Indoor unit EEPROM error 10Indoor unit BLDC fan motor lock or feedback signal absent for 50 seconds.100Discharge temperature excessively high on constant speed compressor 1 of sub1…101Discharge temperature excessively high on constant speed compressor 2 of sub1…102Discharge temperature excessively high on constant speed compressor 1 of sub2…103Discharge temperature excessively high on constant speed compressor 2 of sub2…104Transmission error 105Transmission error between outdoor main PCB and fan main PCB (fan to outdoor…106Over-current of main outdoor fan motor (inverter fan IPM fault).107Low voltage of main outdoor fan motor driver (DC voltage charging failure).108Transmission error between main PCB and fan PCB (main to fan direction).109High pressure switch tripped on sub1 outdoor unit.11Indoor unit transmission error 110Reverse connection or missing phase of 3-phase power on sub1 outdoor unit.111Transmission error 113Liquid pipe (condenser) temperature sensor open or short on main outdoor unit.114Sub-cooling inlet temperature sensor open or short on main outdoor unit.115Sub-cooling outlet temperature sensor open or short on main outdoor unit.116High pressure sensor open or short on sub1 outdoor unit.117Low pressure sensor open or short on sub1 outdoor unit.118Air temperature sensor open or short on sub1 outdoor unit.120Suction temperature sensor open or short on sub1 outdoor unit.121Discharge pipe temperature sensor open or short on sub1 constant compressor 1.

View all 152 error codes

122Discharge pipe temperature sensor open or short on sub1 constant compressor 2.123Front-side heat exchanger pipe temperature sensor open or short on sub1 outdoor…124Rear-side heat exchanger pipe temperature sensor open or short on sub1 outdoor…125Liquid pipe temperature sensor open or short on sub1 outdoor unit.126Sub-cooling inlet temperature sensor open or short on sub1 outdoor unit.127Sub-cooling outlet temperature sensor open or short on sub1 outdoor unit.128High pressure sensor open or short on sub2 outdoor unit.129Low pressure sensor open or short on sub2 outdoor unit.130Air temperature sensor open or short on sub2 outdoor unit.132Suction temperature sensor open or short on sub2 outdoor unit.133Discharge pipe temperature sensor open or short on sub2 constant compressor 1.134Discharge pipe temperature sensor open or short on sub2 constant compressor 2.135Front-side heat exchanger pipe temperature sensor open or short on sub2 outdoor…136Rear-side heat exchanger pipe temperature sensor open or short on sub2 outdoor…137Liquid pipe temperature sensor open or short on sub2 outdoor unit.138Sub-cooling inlet temperature sensor open or short on sub2 outdoor unit.139Sub-cooling outlet temperature sensor open or short on sub2 outdoor unit.140High pressure switch tripped on sub2 outdoor unit.141Reverse connection or missing phase of 3-phase power on sub2 outdoor unit.142Transmission error 143High pressure excessively increased on sub1 outdoor unit.144Low pressure excessively decreased on sub1 outdoor unit.145High pressure excessively increased on sub2 outdoor unit.146Low pressure excessively decreased on sub2 outdoor unit.147Input voltage of sub1 outdoor unit is more than 487V or less than 270V.148Voltage detection circuit of sub1 outdoor unit is out of order.149Input voltage of sub2 outdoor unit is more than 487V or less than 270V.150Voltage detection circuit of sub2 outdoor unit is out of order.1514-way reversing valve function error causing pressure unbalance between outdoor…152Discharge temperature excessively high on constant speed compressor 1 of sub3…153Discharge temperature excessively high on constant speed compressor 2 of sub3…154High pressure switch tripped on sub3 outdoor unit.155Reverse connection or missing phase of 3-phase power on sub3 outdoor unit.156Transmission error 157High pressure sensor open or short on sub3 outdoor unit.158Low pressure sensor open or short on sub3 outdoor unit.159Air temperature sensor open or short on sub3 outdoor unit.161Suction temperature sensor open or short on sub3 outdoor unit.162Discharge pipe temperature sensor open or short on sub3 constant compressor 1.163Discharge pipe temperature sensor open or short on sub3 constant compressor 2.164Front-side heat exchanger pipe temperature sensor open or short on sub3 outdoor…165Rear-side heat exchanger pipe temperature sensor open or short on sub3 outdoor…166Liquid pipe temperature sensor open or short on sub3 outdoor unit.167Sub-cooling inlet temperature sensor open or short on sub3 outdoor unit.168Sub-cooling outlet temperature sensor open or short on sub3 outdoor unit.169High pressure excessively increased on sub3 outdoor unit.170Low pressure excessively decreased on sub3 outdoor unit.171Input voltage of sub3 outdoor unit out of tolerable range.172Voltage detection circuit of sub3 outdoor unit is out of order (sensor…173Abnormal starting of main constant speed compressor (over-increase of…174Abnormal starting of sub1 constant speed compressor 1.175Abnormal starting of sub1 constant speed compressor 2.176Abnormal starting of sub2 constant speed compressor 1.177Abnormal starting of sub2 constant speed compressor 2.200Pipe detection error during auto addressing 201HR unit 1 liquid pipe temperature sensor open or short.202HR unit 1 sub-cooling inlet pipe temperature sensor open or short.203HR unit 1 sub-cooling discharge pipe temperature sensor open or short.204Transmission error between HR unit 1 and outdoor unit.205HR unit 2 liquid pipe temperature sensor open or short.206HR unit 2 sub-cooling inlet pipe temperature sensor open or short.207HR unit 2 sub-cooling discharge pipe temperature sensor open or short.208Transmission error between HR unit 2 and outdoor unit.209HR unit 3 liquid pipe temperature sensor open or short.21IPM fault or overcurrent detected at inverter compressor (U,V,W phases).210HR unit 3 sub-cooling inlet pipe temperature sensor open or short.211HR unit 3 sub-cooling discharge pipe temperature sensor open or short.212Transmission error between HR unit 3 and outdoor unit.213HR unit 4 liquid pipe temperature sensor open or short.214HR unit 4 sub-cooling inlet pipe temperature sensor open or short.215HR unit 4 sub-cooling discharge pipe temperature sensor open or short.216Transmission error between HR unit 4 and outdoor unit.217HR unit 5 liquid pipe temperature sensor open or short.218HR unit 5 sub-cooling inlet pipe temperature sensor open or short.219HR unit 5 sub-cooling discharge pipe temperature sensor open or short.22Overcurrent flowing at CT sensing circuit exceeds maximum allowable value…220Transmission error between HR unit 5 and outdoor unit.221HR unit 6 liquid pipe temperature sensor open or short.222HR unit 6 sub-cooling inlet pipe temperature sensor open or short.223HR unit 6 sub-cooling discharge pipe temperature sensor open or short.224Transmission error between HR unit 6 and outdoor unit.225HR unit 7 liquid pipe temperature sensor open or short.226HR unit 7 sub-cooling inlet pipe temperature sensor open or short.227HR unit 7 sub-cooling discharge pipe temperature sensor open or short.228Transmission error between HR unit 7 and outdoor unit.229HR unit 8 liquid pipe temperature sensor open or short.23DC voltage charging failure for inverter compressor drive after starting relay…230HR unit 8 sub-cooling inlet pipe temperature sensor open or short.231HR unit 8 sub-cooling discharge pipe temperature sensor open or short.232Transmission error between HR unit 8 and outdoor unit.24High pressure switch tripped on main outdoor unit causing compressor shutdown.240Central controller CNU connection failure 241Central controller data transmission error (CNU to central controller sending…242Central controller data receiving error from CNU.243Central controller receive buffer overflow 244Central controller to CNU data transmission failure (receiving timeout exceeds…245Central controller send timeout 246Central controller receive timeout 25Input voltage is out of tolerable range (low or over voltage on main PCB).250Central controller checksum error 251Central controller receive zero error 252Central controller wrong address error 32Inverter compressor discharge temperature excessively high on main outdoor unit…33Constant speed compressor discharge temperature excessively high on main…34High pressure excessively increased on main outdoor unit (3 successive…35Low pressure excessively decreased on main outdoor unit (3 successive…40Low current detected at CT sensor 41Inverter compressor discharge pipe temperature sensor open or short on main…42Low pressure sensor open or short on main outdoor unit.43High pressure sensor open or short on main outdoor unit.44Outdoor air temperature sensor open or short on main outdoor unit.45Front-side heat exchanger temperature sensor open or short on main outdoor unit.46Suction temperature sensor open or short on main outdoor unit.47Constant speed compressor discharge pipe temperature sensor open or short on…48Rear-side heat exchanger temperature sensor open or short on main outdoor unit.51Sum of connected indoor unit capacity exceeds 130% of outdoor unit rated…52Transmission error from inverter PCB to main PCB on outdoor unit.53Transmission error from indoor unit to main PCB of outdoor unit.54Reverse connection or missing phase of R,S,T power supply on main outdoor unit.57Transmission error from main PCB to inverter PCB on outdoor unit.62Overheat of inverter heatsink on outdoor unit.65Heat sink temperature sensor of inverter control PCB is open or short.

Service modes (5)

auto_addressing1
forced_operationPress the forced operation (power) button on the indoor unit once.
initial_setup1. Set all DIP switches before power ON. 2. Apply power. 3. Step 1
instant_indoor_unit_checking1. Set DIP switch on outdoor main PCB
test_operationPress and hold the ON/OFF (forced operation) button on the indoor unit for 3-5 seconds until a…

Full entry steps, exit procedures, and test sequences are available in Max.

Related LG air conditioner models

75,000+ service documents · 20,000+ error codes · 100+ brands

$29/month · Cancel anytime · Or $9.95 3-day pass · Plus applicable tax