Kenmore Dishwasher Error Code 6-4

Code 6-4 means the control board detected the overfill float switch in the open position, indicating the dishwasher may have too much water in the tub or there is a fault in the float switch circuit. The board uses this signal to prevent flooding. The root cause could be a stuck float, a failed switch, a fill valve that will not close, a leaking drain check valve, or excessive suds lifting the float prematurely.

Running the dishwasher with an active 6-4 code carries a risk of overflow if the underlying cause is a fill valve stuck open or a failed float switch. The safety circuit that is supposed to stop filling is not functioning reliably. Avoid running full cycles until the float, switch, and fill valve have been inspected and confirmed working correctly.

If the fix is simply clearing debris from the float or adjusting leveling legs, the repair costs nothing beyond your time. A replacement float switch typically costs between $15 and $40 for the part, and most homeowners with basic tools can replace it in under an hour. A failed fill valve runs $20 to $60 for the part. A shorted fill valve triac requiring control board replacement is the most expensive scenario, with boards ranging from $100 to $250 or more depending on the model. If both the board and valve have failed, professional diagnosis is advisable before ordering parts.

Start by removing the bottom rack and locating the float, which is a small dome on the tub floor. Clear any debris from around it, lift it manually, and confirm you hear a click when it drops back down. Next, verify the dishwasher is level using a bubble level on the tub floor. If the float moves freely and the unit is level, use a multimeter to measure resistance across the float switch terminals under the tub. A reading of open circuit with the float in the down position means the switch needs replacement. If the switch tests good, inspect the fill valve and drain check valve for failure.

Yes. Excessive suds can physically raise the float even when the actual water level is within the normal range, triggering the overfill switch and producing a 6-4 code. This typically happens after using hand dish soap or too much detergent. Run a rinse cycle with no detergent, or place a small amount of cooking oil in the tub to break down the suds, then check whether the code clears.