KitchenAid Dishwasher Error Code OP

The OP code means the control board has detected an open circuit at the thermistor connector, indicating it cannot receive a temperature signal from the thermistor. This is typically caused by a disconnected wiring harness, a broken wire, or a thermistor that has failed internally. The dishwasher will not operate normally until the fault is resolved to prevent uncontrolled water heating.

It is not recommended to continue running the dishwasher while the OP code is active. Without a functioning thermistor signal, the control board cannot accurately monitor water temperature, which could lead to improper wash performance or heating issues. Resolve the fault before resuming normal use.

Repair costs vary depending on the cause. If the issue is simply a loose connector, no parts are needed and a service call fee is the primary expense, typically in the range of $75 to $150. Thermistor replacement parts generally cost between $20 and $60, with total repair costs including labor ranging from $100 to $250. A control board replacement, if needed, is considerably more expensive and may range from $200 to $450 or higher.

Start by checking that the thermistor connector is fully seated at the control board and reseat it if it appears loose. If the connection is secure, use a multimeter to check the wiring for continuity and test the thermistor itself for resistance. A thermistor reading infinite resistance has failed and will need to be replaced. If wiring and the thermistor check out, the control board may require evaluation.

A reset may temporarily clear the OP code from the display, but the error will return if the underlying cause has not been corrected. If the thermistor is disconnected or has failed, the control board will detect the open circuit again as soon as the next cycle begins. A permanent fix requires repairing or replacing the faulty component.