Samsung Air Conditioner Error Code OUTDOOR_YELLOW_RED_ON

This error indicates that the outdoor unit has detected a fault in one or more of its outdoor temperature sensors. The fault is classified as either an open circuit, where continuity is lost, or a short circuit, where resistance drops to near zero. The control board cannot interpret either condition as a valid temperature reading, so it generates this alert. The system may limit or suspend operation until the sensor circuit is restored to a normal resistance range.

It is not recommended to continue running the unit with this error present. The outdoor temperature sensors are used by the control board to protect the compressor and manage defrost cycles. Operating without valid sensor data can lead to compressor damage or unsafe operating conditions. Address the fault before resuming normal use.

Repair costs vary depending on the root cause. A replacement outdoor thermistor is typically an inexpensive part, often in the range of $15 to $60 for the component alone. If professional labor is required for diagnosis and replacement, total costs generally fall between $100 and $300 depending on local rates and accessibility of the unit. A faulty outdoor control board is the most expensive scenario, with parts and labor potentially ranging from $300 to $600 or more.

Start by using a multimeter to measure the resistance of the outdoor temperature sensor and compare it to the expected value for the current ambient temperature. Inspect all sensor wiring and connector pins for corrosion, breaks, or moisture damage. If the sensor resistance is out of range and wiring is intact, replace the thermistor. If the sensor and wiring are both within specification, the outdoor control board may need further evaluation.

A power reset may temporarily clear the error display, but the code will return if the underlying sensor fault has not been repaired. Because the error is tied to a measured electrical condition in the sensor circuit, the control board will re-detect the fault as soon as it reads the sensor again. A reset alone is not a fix and should not be relied on as a solution.