Kenmore Dishwasher Error Code 3-1

Error code 3-1 means the control board has detected an open circuit in the temperature sensing circuit. The dishwasher is not receiving a valid signal from the temperature sensor (thermistor) that monitors water temperature. The cause is typically a failed sensor, a broken wire in the harness, or a corroded connector rather than the control board itself.

Running the dishwasher with an active 3-1 code is not recommended. Without a functioning temperature sensor, the control board cannot monitor water temperature, which means the dishwasher may not heat water properly or may run cycles that do not fully sanitize dishes. Continuing to operate it could also prevent the fault from being properly diagnosed and may result in incomplete wash cycles or the machine stopping mid-cycle.

Unplug the dishwasher, locate the temperature sensor inside the tub (usually near the bottom), and disconnect its wiring connector. Set a multimeter to resistance (ohms) mode and probe the two sensor terminals. At room temperature, a working thermistor should show a resistance reading rather than an open line (OL) or infinite reading. You can also place the sensor in warm water and verify the resistance value changes as temperature increases. An open or unchanging reading confirms the sensor has failed and needs replacement.

Start by running the service diagnostics cycle to check sensor operation, then unplug the dishwasher and use a multimeter to test resistance across the temperature sensor and continuity through the wiring harness. A functioning thermistor will show a measurable resistance that changes with temperature; an open reading confirms a bad sensor. If the sensor and wiring both test good, the control board input is suspect. Most repairs involve replacing the thermistor or repairing a connector, both of which are manageable DIY tasks with basic tools.

If the temperature sensor (thermistor) is the cause, the part typically costs between $15 and $40 depending on the specific Kenmore model. If a wiring harness section needs replacement, parts are in a similar range. DIY repair is achievable for most homeowners comfortable with a multimeter and basic disassembly. A professional repair technician will add a service call and labor fee, usually bringing the total to $100 to $200. If the control board input has failed, board replacement costs significantly more, making professional diagnosis worthwhile before purchasing that part.