LG Air Conditioner Error Code E355

E355 means the Intelligent Power Module for the Fan2 circuit has reached or exceeded its maximum safe internal temperature of 85 degrees Celsius. The unit shuts down automatically to prevent permanent damage to the IPM electronics. The most common triggers are blocked heat sink fins, a failing fan motor, or poor ventilation around the outdoor unit. The error must be resolved before the unit will operate normally again.

No. The E355 error triggers an automatic shutdown specifically to prevent heat damage to the IPM and surrounding components. Attempting to override or repeatedly reset the unit without addressing the root cause can lead to permanent damage to the power module, which is a costly repair. Leave the unit powered off until the cause of the overheating is identified and corrected.

Repair costs vary widely depending on the cause. Cleaning a blocked heat sink is essentially free if done yourself, or may cost between $75 and $150 for a service call. Replacing the Fan2 motor typically runs between $150 and $400 including parts and labor. If the IPM module itself has failed and requires replacement, costs can range from $300 to $700 or more depending on the unit model and technician rates.

Some causes of E355 are accessible to a knowledgeable DIYer, such as clearing debris from the heat sink fins or confirming the fan blade spins freely after powering off the unit. However, tasks like replacing the IPM module or the Fan2 motor involve high-voltage components and should be handled by a qualified technician. Always disconnect power completely before inspecting any internal components.

A power reset may temporarily clear the error code, but if the underlying cause such as a blocked heat sink or a failing fan motor is not corrected, the E355 will return once the IPM temperature climbs again. A reset alone is not a repair. The error code will continue to recur until the physical or electrical cause of the overheating is resolved.