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Error code reference

Daewoo Air Conditioner Error Code 1 blink

Indoor coil sensor open or short, OR outdoor coil sensor open or short, OR compressor or electrical parts of…

Daewoo codesDaewoo air conditioner codes

Indoor coil sensor open or short, OR outdoor coil sensor open or short, OR compressor or electrical parts of compressor error — unit does not work.

First step from the service manual

Check sensor open/short: Micom input voltage 0~0.3V indicates open, 4.7~5.0V indicates short. For compressor error, check if indoor coil temperature change is below +/-2°C after 5 minutes of compressor operation.

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

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What 1 blink means on a Daewoo air conditioner

The 1 blink error code on a Daewoo air conditioner signals one of three distinct fault conditions: an open or short circuit in the indoor coil temperature sensor, the same type of fault in the outdoor coil temperature sensor, or a compressor or compressor electrical parts error. Because all three conditions share the same blink code, technicians must work through a structured diagnostic sequence to isolate the actual fault. In every case, the unit will not operate until the fault is resolved and the system is cleared.

For sensor faults, the diagnostic process focuses on the Micom (microcontroller) input voltage at the sensor circuit. A reading of 0 to 0.3V indicates an open circuit condition, meaning the sensor circuit is broken, typically due to a failed thermistor, a disconnected connector, or damaged wiring. A reading of 4.7 to 5.0V indicates a short circuit, where the sensor leads or wiring have shorted together or to ground. Both conditions prevent the Micom from receiving valid temperature data, triggering the fault.

For a compressor or compressor electrical parts error, the diagnostic approach shifts to monitoring the indoor coil temperature over time. If the indoor coil temperature does not change by at least plus or minus 2 degrees Celsius within 5 minutes of compressor operation, the Micom registers a compressor fault. This can point to a failed compressor, a refrigerant charge problem, or a fault in the electrical components driving the compressor, such as a capacitor or contactor. Accurate voltage measurement and temperature monitoring are both essential to correctly identifying which of the three fault types is present.

Source: manufacturer service documentation.

Common causes of 1 blink

  1. 01

    Failed indoor or outdoor coil thermistor

    Part replacement

    The thermistor sensor has degraded or failed, causing the Micom input voltage to fall outside the normal operating range. This is confirmed by measuring the input voltage at the sensor circuit and finding a reading of 0 to 0.3V for an open or 4.7 to 5.0V for a short.

  2. 02

    Loose or disconnected sensor wiring connector

    Wiring / connection

    A connector on the indoor or outdoor coil sensor harness has worked loose or become disconnected, producing an open circuit voltage reading of 0 to 0.3V at the Micom input. Inspecting and reseating all sensor connectors should be done before replacing any parts.

  3. 03

    Damaged sensor wiring

    Part replacement

    The wiring between the coil sensor and the Micom control board may have chafed, corroded, or shorted, producing either a low or high voltage reading at the input. Visual inspection of the full wiring harness for damage or pinching is required to identify this cause.

  4. 04

    Compressor failure or compressor electrical parts fault

    Part replacement

    If the indoor coil temperature does not shift by at least plus or minus 2 degrees Celsius after 5 minutes of compressor run time, the compressor itself or its associated electrical components such as the run capacitor may be faulty. This requires checking compressor operation and the electrical parts in the compressor circuit.

  5. 05

    Low or lost refrigerant charge

    Wiring / connection

    Insufficient refrigerant can prevent the indoor coil from showing the expected temperature change during compressor operation, causing the Micom to log a compressor error. A manifold gauge check of system pressures will confirm if refrigerant level is the contributing factor.

See the test procedure for each cause

Frequently asked questions about 1 blink

What does 1 blink mean on a Daewoo air_conditioner?
A 1 blink error on a Daewoo air conditioner indicates one of three fault conditions: an open or short circuit in the indoor coil sensor, the same fault in the outdoor coil sensor, or an error related to the compressor or its electrical parts. In all cases, the unit will stop operating until the fault is diagnosed and corrected. Technicians determine the specific cause by measuring the Micom sensor input voltage and monitoring indoor coil temperature during compressor operation.
Can I fix the 1 blink error on my Daewoo air conditioner myself?
Some causes, such as a loose sensor connector, can be checked by a knowledgeable DIYer after safely disconnecting power to the unit. However, diagnosing the fault accurately requires a multimeter to measure sensor circuit voltages and the ability to monitor coil temperatures during compressor operation, which goes beyond basic DIY skill. Compressor and refrigerant-related faults should be handled by a certified technician.
Is it safe to keep running my Daewoo air conditioner when it shows the 1 blink error?
No. The 1 blink error causes the unit to shut down and not operate, which is the system protecting itself from running in a faulty or unsafe condition. You should not attempt to force the unit to run while this fault is active. Leave the unit powered down until the fault has been properly diagnosed and resolved.
Will resetting the unit clear the 1 blink error on a Daewoo air conditioner?
A power reset may temporarily clear the error display, but it will not fix the underlying problem. If the sensor is failed, the wiring is damaged, or the compressor has a fault, the 1 blink code will return once the unit attempts to operate again. The root cause must be identified and corrected for the error to clear permanently.
How much does it cost to repair the 1 blink error on a Daewoo air conditioner?
Repair costs depend on which component is at fault. Replacing a coil temperature sensor is generally a lower-cost repair, typically in the range of $50 to $150 including parts and labor. Compressor replacement or refrigerant service is significantly more expensive, often ranging from $300 to $800 or more depending on the unit size and local labor rates. Getting a proper diagnosis first will help avoid unnecessary parts replacement.

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