Skip to main content
LG HVAC Error Codes
76 error codes for LG hvac models. Each links to the full diagnostic procedure from the service manual.
CodeDescription
1PCB sees IDU pipe or air thermistor as open or shorted (varies by unit type10LS902HPV/LS122HPV/LA09xHV/LA12xHV12PCB sees IDU middle pipe thermistor as open or shorted.13Reactor or electronic noise filter failure in ODU.14Compressor Phase Amperage Error.2PCB sees ODU or IDU thermistor(s) as open or shorted (varies by unit type21Inverter compressor high amperage.22Inverter unit high amperage.23Inverter DC link voltage too low.24High or low pressure switch open (low opens at 14 PSI, high at 600 PSI).25Low voltage or high voltage feeding unit.26Inverter compressor seized, not rotating or not proving rotation.27Inverter compressor amperage over 100A for a split second.28Inverter DC link voltage too low.29Inverter compressor high amperage.310/13 SEER Flex Multi32Inverter compressor discharge pipe temperature 105°C/220°F or higher.33Single speed compressor discharge pipe temperature 105°C/220°F or higher.34High pressure switch opened, over 600 PSI.35Low pressure switch opened, under 14 PSI.MyPros+ Max
Get the full diagnostic procedure for any LG hvac error code.
- Step-by-step tests with expected resistance, voltage, and continuity values
- Wiring diagram references and connector pinouts
- Verified part numbers when replacement is required
Get started
$29/month · Cancel anytime · Or $9.95 3-day pass
4LA09xHV/LA12xHV/LS902HPV/LS122HPV40Inverter PCB amperage sensing circuit failure.41PCB sees inverter compressor discharge pipe thermistor as open or shorted.42Low pressure switch opened, under 14 PSI.43High pressure switch opened, over 600 PSI.44PCB sees ODU air sensor as open or shorted.45PCB sees ODU condenser coil middle or exit pipe (liquid line) thermistor as…46PCB sees ODU suction line thermistor as open or shorted.47PCB sees ODU single-speed compressor discharge pipe thermistor as open or…48PCB sees ODU coil outlet (liquid line) thermistor as open or shorted.4913 SEER Split/Multi Split5Communication error between IDU and ODU PCB.51Flex Multi cannot exceed 130% indoor units relative to outdoor.52ODU communication error between inverter PCB and main outdoor unit PCB.53Communication error; #3 communication wire not properly connected to ODU PCB.543-phase wiring issue.57Communication error between outdoor main PCB and inverter PCB.6LA09xHV/LA12xHV/LS902HPV/LS122HPV60EEPROM failure.61PCB sees condenser coil over 65°C/149°F (sensed at ODU in cool mode and IDU in…62Inverter ODU PCB heat sink temperature 85°C/185°F or higher.63Condenser coil pipe sensor temperature low (opposite to error code 61), sensed…65Outdoor unit inverter heat sink temperature sensor fault.67ODU fan motor not rotating or not proving rotation.7Flex Multi73Inverter compressor drawing over 48 amps.8IDU fan motor not rotating or not proving rotation.89Flex Multi LMUxxxHV units DIP Switch 3 configuration error on outdoor PCB.9LS902HPV/LS122HPV/LA09xHV/LA12xHVCAPCB sees ODU discharge pipe thermistor as open or shorted.CC13 SEER Flex Multi (with dual single speed compressors) EEPROM error; too much…CdReactor or electronic noise filter failure in ODU (copper coil around magnet).CECompressor Phase Current Error.CH01Indoor thermistor open or short circuit error, causing operation to turn off.CH02Outdoor thermistor open or short circuit error, causing operation to turn off.CH03Remote controller communication error, causing operation to turn off.CLChild Lock is engaged (not an error).COPCB sees IDU air thermistor as open or shorted.E121Indoor temperature sensor error (short or open circuit).E139CO2 sensor error (short or open circuit); CO2 input pulse maintains High or Low…E153EEPROM error (EEPROM error count >= 5 failures during read/write test).E201MASTER ERV tracking errorE202System failure by communication errorE221Outdoor temperature sensor error (short or open circuit).E561Supply air (SA) fan motor errorE562Exhaust air (EA) fan motor errorE601Communication error between the wired remote control and the ventilatorE606COM1/COM2 cross installation errorE652Communication error by installing COM1 dual MASTERE654Damper errorF1Low speed fan on PTAC, this is normal operation.F2High speed fan on PTAC, this is normal operation.HLCondensate pump float switch risen/open, or all system functions locked via…PFPTAC Freeze Protection mode; indoor air thermistor shows PCB room temp less…PoJet Cool Mode active (not an error).REPTAC set for wall-mount thermostat by DIP switch 1 in on position.