LG · Air Conditioner error code
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Guide · Air ConditionerMost communication faults are wiring: swapped terminals, loose screws, splices or damaged cable, often after a new install or a storm. Check power, then terminations at both ends, then the data signal, before replacing a board.
Guide · Air ConditionerCommunication codes are usually about the path between the boards, not the boards: loose or swapped terminals, a splice in the interconnect cable, solid or undersized wire, noise from nearby line-voltage runs, or a damaged cable. The wrong turn is replacing boards on the code alone; prove the interconnect first.
Component test · Air ConditionerMini-split outdoor boards rectify line voltage to a high DC bus and drive the compressor and fan. Field checks are input power, communication, error codes and compressor winding balance. Board DC bus voltage is dangerous after shutdown.
LG · Air Conditioner
CH 09
Indoor board EEPROM error
LG · Air Conditioner
CH 10
Indoor fan motor error
LG · Air Conditioner
CH 12
Indoor middle pipe thermistor open/short
LG · Air Conditioner
CH 21
DC peak / IPM fault (inverter)
LG · Air Conditioner
CH 22
CT2 error: AC input current too high
LG · Air Conditioner
CH 23
DC link voltage too low