LG Heat Pump Error Code E163

E163 indicates a fault with the 2nd MCU solenoid valve in the LG heat pump system. This solenoid valve controls refrigerant flow in a specific circuit, and the control system has detected an abnormal or missing signal from this component. The fault may be in the valve itself, the wiring, or the control board driving it.

Operating the unit with E163 active is not recommended. A faulty solenoid valve can cause improper refrigerant routing, which may lead to compressor damage, reduced efficiency, or system short-cycling. It is best to shut the unit down and have it inspected before continued use.

A power reset may temporarily clear the E163 error, but if the underlying fault with the solenoid valve or its wiring remains, the code will return once the system attempts to operate that circuit again. A reset is useful for ruling out a one-time glitch but is not a substitute for proper diagnosis and repair.

Basic checks such as inspecting visible wiring for damage or loose connectors are within reach for a knowledgeable DIYer. However, diagnosing and replacing the solenoid valve or control board requires electrical testing skills and involves the refrigerant circuit, which must be handled by a certified HVAC technician in most regions. Attempting refrigerant-side repairs without proper certification is not recommended.

Repair costs vary depending on the failed component. Wiring harness repairs or connector replacement are typically lower cost, generally in the range of $75 to $200 including labor. A solenoid valve replacement may run $150 to $400 or more depending on parts availability and labor rates. Control board replacement tends to be the most expensive repair, often ranging from $300 to $700 or higher.