Bosch Refrigerator Error Code Er rt

The Er rt error code on a Bosch refrigerator indicates a fault with the ambient temperature sensor, specifically either an interruption (open circuit) in the sensor circuit or a short-circuit condition. This sensor monitors the temperature of the surrounding environment and feeds that data to the control system, which uses it to regulate cooling performance and adapt operation to room conditions. When the control board detects a signal that falls outside the expected resistance or voltage range for the sensor, it logs the Er rt fault and may alter or suspend normal refrigeration cycles.

The critical detail with this fault is that the ambient temperature sensor is physically integrated into the control electronics module itself. It is not a standalone component with a separate connector or wiring harness that can be tested and swapped independently. Because the sensor is embedded directly on the control board, standard sensor diagnostics such as checking resistance across terminals or testing sensor wiring in isolation are not applicable in the usual way. The fault is essentially inseparable from the module it resides on.

This design means the repair path is straightforward but not inexpensive: the entire control electronics module must be replaced. Causes typically include internal failure of the sensor element on the board due to age, heat stress, power surges, or moisture intrusion affecting the electronics. There is no adjustment, reset, or partial repair that will resolve a confirmed sensor failure on this integrated assembly.