LG Air Conditioner Error Code E393

E393 indicates an output current sensor error on the outdoor Fan2 PCB. The system detected an abnormal current signal from the circuit board that controls and monitors the second outdoor condenser fan. LG's diagnostic guidance points to checking the power connection at the Fan2 PCB and replacing the board if the fault persists.

Operating the system with an active E393 error is not recommended. The outdoor fan circuit affected by this fault may not be running properly, which can lead to inadequate condenser cooling and potential damage to the compressor from elevated head pressure. The system should be diagnosed and repaired before returning it to regular use.

A power reset may temporarily clear the E393 error code, but if the underlying fault in the Fan2 PCB or its associated wiring still exists, the error will return once the system attempts to operate the fan circuit again. A reset alone does not fix the hardware issue. The root cause must be identified and corrected for the fault to be resolved permanently.

Checking and reseating the power connections at the outdoor Fan2 PCB is something a confident DIYer can attempt after disconnecting power to the unit. However, diagnosing whether the fault is in the PCB, the wiring harness, or the fan motor requires electrical testing. If the board needs replacement, a qualified technician is recommended to ensure correct installation and safe handling of high-voltage components in the outdoor unit.

Repair costs depend on the actual root cause. If only a wiring connection needs to be corrected, costs may be limited to a service call fee, typically in the range of $75 to $150. If the Fan2 PCB requires replacement, parts and labor combined can range from $200 to $500 or more depending on the unit model and regional labor rates. A failed fan motor would add additional parts cost on top of that.