Daewoo Air Conditioner Error Code ON LAMP Blink (0.5s, 2 times blink)

This blink pattern indicates the control board has detected one of three faults: an open or shorted outdoor coil temperature sensor, a problem with the compressor or its electrical components, or a refrigerant gas leak. The unit continues to run while the fault is active, but the underlying issue needs to be diagnosed and corrected. A technician should inspect the outdoor unit to identify which of the three fault categories is responsible.

The unit is designed to continue operating with this fault active, but running it with a low refrigerant charge or a failing compressor can cause additional damage over time. Continued operation with these underlying conditions can shorten the life of the compressor significantly. It is best to limit use and have the unit inspected promptly rather than running it indefinitely in a fault state.

Repair costs vary depending on which component is at fault. Replacing an outdoor coil sensor is typically a lower-cost repair, often in the range of $75 to $200 including parts and labor. Compressor capacitor replacement generally falls in a similar range, while compressor replacement or refrigerant leak repair and recharge can cost significantly more, often between $300 and $900 or higher depending on system size and refrigerant type. A diagnostic visit from a technician will help narrow down the actual cost.

Some causes, such as checking and reseating the outdoor coil sensor connector or inspecting wiring for visible damage, are within reach of a knowledgeable DIYer. However, testing compressor windings, measuring capacitor capacitance, and checking refrigerant pressures require specialized tools and, in the case of refrigerant work, EPA certification. It is strongly recommended to have a licensed technician handle compressor and refrigerant-related diagnostics.

Resetting the unit by cycling power may temporarily clear the displayed fault, but the error will return if the underlying problem has not been corrected. A reset does not repair a failed sensor, a degraded compressor capacitor, or a refrigerant leak. Clearing the code without addressing the root cause only delays proper diagnosis and can allow further damage to develop.