LG Air Conditioner Error Code E491

The E491 code indicates an error related to the Fan1 DataFlash memory, which is a flash memory chip embedded in the fan motor control board. This chip stores the operational parameters and configuration data the fan motor needs to function. When the system detects a problem reading or writing this memory, it displays E491 and may shut down fan operation to prevent further issues.

It is not recommended to continue operating the unit while the E491 error is active. A compromised fan motor controller can lead to inadequate cooling, overheating of internal components, or further electrical damage. The unit should be powered off until the fault is diagnosed and resolved.

Repair costs depend on which component has failed and labor rates in your area. Replacing a fan motor control board typically ranges from $150 to $450 including parts and labor, while a full fan motor assembly replacement may run $200 to $600 or more. Obtaining a diagnosis from a certified technician first will help clarify exactly which component needs to be replaced.

This error involves a hardware-level memory fault on the fan motor control board, which makes it difficult for most homeowners to resolve without technical experience. Checking and reseating wiring harnesses connected to the fan motor is a safe first step, but if the fault persists, the control board or fan motor assembly will likely need professional diagnosis and replacement.

A power reset may temporarily clear the error display, but because E491 points to a hardware fault in the DataFlash memory chip, the code will typically return once the system restarts and attempts to communicate with the fan motor controller again. A lasting fix requires inspection and likely replacement of the affected board or motor assembly.