LG Air Conditioner Error Code 108

Error code 108 on an LG air conditioner indicates a communication error between the main outdoor unit control PCB and the fan driving control PCB. The fan control board is not receiving the expected signal from the main outdoor board. This prevents proper fan motor operation and causes the system to shut down. The issue is located entirely in the outdoor unit.

No. Error code 108 means the outdoor fan motor is not being properly controlled, and the system will typically shut down automatically to prevent compressor overheating. Attempting to force the unit to run without a functioning outdoor fan can cause severe compressor damage. The error should be resolved before normal operation is resumed.

Repair costs vary depending on the cause. If the fix is a reseated or cleaned connector, the cost may be limited to a service call fee, typically in the range of $75 to $150. If a fan driving PCB or main outdoor PCB replacement is needed, parts and labor combined can range from $200 to $600 or more depending on the specific model and local labor rates.

A knowledgeable DIYer can inspect the wiring harness and connectors between the two outdoor PCBs for looseness, corrosion, or visible damage, and reseat or clean connections without special tools. However, if a circuit board replacement is needed, working inside the outdoor unit involves high-voltage components, so that work is best left to a certified technician. Always disconnect power before inspecting any wiring inside the unit.

A power reset may temporarily clear the fault display, but if the underlying communication wiring or board issue has not been corrected, the error will return as soon as the system attempts to operate the outdoor fan again. A reset is useful as a first step to confirm whether the fault is intermittent, but it is not a repair.