LG Heat Pump Error Code E302

E302 indicates a breakaway fault on the OUT-TEMP sensor, which is the outdoor ambient temperature sensor. The control board is not receiving a valid signal from this sensor, either because the sensor has failed, a wiring connection has separated, or the harness has been damaged. The system shuts down or restricts operation to protect the compressor until the fault is resolved.

You should not attempt to bypass or ignore the E302 fault. The outdoor temperature sensor provides data that the system uses for compressor protection and defrost control. Operating without a valid sensor reading could allow the compressor to run under conditions that cause premature wear or damage. Keep the unit off until the fault is diagnosed and corrected.

A power reset may temporarily clear the fault display, but if the underlying sensor or wiring problem is still present, E302 will return as soon as the system attempts to read the outdoor temperature. Resetting alone does not repair a broken sensor connection or a failed sensor. A proper diagnosis and repair of the root cause is necessary for the error to clear permanently.

Some causes of E302 are accessible to a knowledgeable DIYer, such as reseating a loose connector or visually inspecting the wiring harness for obvious damage. However, testing sensor resistance and diagnosing control board faults requires a multimeter and familiarity with HVAC wiring. If you are not comfortable working inside the outdoor unit, a qualified technician should perform the diagnosis.

If the fix is simply reseating a loose connector or cleaning corroded pins, labor costs may be modest, typically in the range of $75 to $150 for a service call. If the outdoor temperature sensor itself needs replacement, parts and labor combined often fall in the range of $150 to $350, depending on the specific model and local labor rates. A control board replacement, if required, would be considerably more expensive.