Haier Refrigerator Error Code 3rd LED Refrigerator flash

The 3rd LED flash pattern on a Haier refrigerator indicates a fault with the R2 SNR sensor, which is the second refrigerator temperature sensor. This sensor is physically mounted on the side wall of the refrigerator compartment and is responsible for monitoring air temperature in that zone. The control board reads the signal from this sensor continuously, and when the resistance or voltage output falls outside the expected operating range, or if the signal is lost entirely, the board triggers this fault code to alert that temperature monitoring in that location has been compromised.

Temperature sensors in refrigerators are typically NTC (negative temperature coefficient) thermistors, meaning their electrical resistance decreases as temperature increases. If the sensor's resistance reading is too high, too low, or completely open or shorted, the control board interprets this as a failure condition. Common failure modes include physical damage to the sensor body, moisture intrusion causing corrosion at the connector terminals, or a break in the wiring harness between the sensor and the control board. Because this sensor sits on the side wall of the refrigerator compartment, it is exposed to condensation cycles that can accelerate connector corrosion over time.

When this error is active, the refrigerator may continue to operate using default or backup temperature parameters, but accurate temperature regulation in the refrigerator compartment cannot be guaranteed. Resolving the fault requires inspecting the sensor, its wiring harness, and the connector at the control board to determine whether the issue is a failed sensor component or a wiring and connectivity problem.