GE Refrigerator Error Code bAd

The bAd error code appears on GE refrigerators during diagnostic mode 07, which is the sensor system test. It indicates that a thermistor in the refrigerator's sensor network is either electrically open (a broken or disconnected circuit) or shorted (an unintended electrical connection causing abnormally low resistance). Thermistors are negative temperature coefficient (NTC) resistors that change resistance in a predictable way as temperature changes. When the control system reads a resistance value that falls outside the expected range for any given temperature, it flags the sensor as faulty and triggers this code.

The primary diagnostic step is to measure the thermistor resistance at connector K5 on the power supply board and compare that reading against the thermistor resistance chart for the unit. An open thermistor will typically show infinite or very high resistance, while a shorted thermistor will read near zero ohms. Neither condition allows the control board to accurately interpret cabinet or evaporator temperatures, which can lead to improper cooling, compressor run issues, or erratic defrost cycles.

Common causes include wiring harness damage between the thermistor and the power supply board, connector corrosion or looseness at K5, and physical failure of the thermistor sensor itself due to age or moisture intrusion. Before replacing any components, technicians should verify the integrity of the wiring and connector first, as a poor connection at K5 can produce the same open-circuit reading as a failed thermistor.