Kenmore Dishwasher Error Code 8-4

Error code 8-4 means the control board has detected an electrical problem in the drain motor circuit. The fault could be a loose wiring connection, an open winding inside the drain motor, a blown fuse on the control board, or a failed drain motor drive circuit. Unplugging the dishwasher and testing the drain motor's winding resistance with a multimeter is the recommended first step.

Running the dishwasher with an 8-4 error active is not advisable. Because this fault is in the drain motor circuit, the dishwasher will likely be unable to complete a drain cycle, leaving standing water in the tub. Continuing to run cycles in this condition can promote mold growth and may allow water to overflow or leak. Diagnose and repair the fault before resuming normal use.

Disconnect power to the dishwasher before any testing. Locate the drain motor and unplug its wiring harness, then set a multimeter to measure resistance (ohms) and probe the motor's two terminals. A healthy drain motor winding typically shows a low, finite resistance reading; an open reading (OL or no continuity) confirms the winding has failed and the motor must be replaced. Also check each connector in the harness for corrosion or damage before concluding the motor itself is at fault.

Start by disconnecting power to the dishwasher and inspecting all wiring connectors in the drain motor circuit for looseness or corrosion. Use a multimeter to measure the resistance of the drain motor windings; an open reading (OL or infinite) means the motor needs replacement. Also check the fuse on the control board's drain motor circuit. If the motor and wiring test good but the code persists, the control board's drain motor drive circuit has likely failed and the board will need to be replaced.

Repair cost depends on which component has failed. Cleaning or reseating a loose connector costs nothing beyond your time. A replacement drain motor typically runs $40 to $100 in parts, and a replacement control board ranges from $80 to $200 depending on the model. If you hire a technician, expect to add $80 to $150 in labor. Testing the wiring and motor yourself first can help you avoid unnecessary parts purchases.