Kenmore Refrigerator Error Code R1 R5 ON

The R1 R5 ON error code on a Kenmore refrigerator indicates that the ambient (room temperature) sensor, also referred to as the RT sensor, has been detected as either open circuit or short circuit. This sensor monitors the temperature of the surrounding environment and feeds that data to the refrigerator's control board, which uses it to regulate compressor cycles, fan operation, and overall cooling performance. When the control board cannot receive a valid signal from this sensor, it triggers the R1 R5 ON alert to flag the fault.

An open circuit condition means the electrical path through the sensor has been broken, resulting in no signal reaching the control board. A short circuit condition means the sensor's resistance has dropped abnormally low, sending an out-of-range signal. Both conditions prevent accurate ambient temperature readings. Thermistor-type sensors like the RT sensor typically exhibit predictable resistance values at given temperatures, so any reading that falls outside the expected range will register as a fault.

The first diagnostic step is to check each sensor involved. This means physically inspecting the RT sensor and its wiring harness for damage, corrosion, or disconnected connectors. A technician should also use a multimeter to measure the sensor's resistance and compare it against the specified value for the current ambient temperature. A reading of zero ohms suggests a short, while an infinite or very high resistance reading suggests an open circuit. If wiring checks out, the sensor itself is likely faulty and will need replacement.