Daewoo Microwave Error Code ERR 1

ERR 1 indicates that the microwave's control board has detected a short circuit in the thermistor circuit, specifically a resistance reading of 0 ohms. The thermistor is the internal temperature sensor the microwave uses to monitor heat during operation. When a short is detected, the unit shuts down to prevent thermal damage. The thermistor itself or the PCB will need to be tested and likely replaced.

Start by testing the thermistor with a multimeter set to measure resistance. If the reading is 0 ohms, the thermistor is shorted and needs to be replaced. If the thermistor resistance appears normal, the fault is likely on the control board (PCB), which would then require inspection or replacement. Both the thermistor and PCB connections and wiring should also be visually inspected for damage.

If only the thermistor needs replacement, parts and labor typically cost in the range of $50 to $150 depending on the model and service provider. If the control board (PCB) is at fault, repair costs can rise to the $100 to $250 range or higher. In some cases where the microwave is older or the PCB cost is high, replacement of the entire unit may be more economical.

Unplugging the microwave and plugging it back in may temporarily clear the display, but ERR 1 will return as soon as the control board polls the thermistor circuit and detects the short again. The underlying fault, a shorted thermistor or PCB issue, must be repaired before the error will stay cleared.

No, the microwave should not be used while ERR 1 is active. The error means the temperature sensor is non-functional, so the control board cannot monitor internal temperatures during a cooking cycle. Operating without a working thermistor removes a layer of thermal protection and could allow unsafe heat buildup inside the unit.