Bosch Dishwasher Error Code F88

F88 on a Bosch dishwasher indicates a turbidity sensor fault, specifically involving component B3/10 and its connection to the electronic control board. The turbidity sensor normally monitors how dirty the wash water is so the dishwasher can adapt cycle settings automatically. When this sensor circuit fails, the dishwasher logs F88 and continues running using fixed default settings instead. The error points to a wiring, connection, or sensor issue that needs to be diagnosed and repaired.

A reset may temporarily clear the F88 code, but it will return if the underlying sensor or wiring fault has not been corrected. Resetting is useful for confirming whether the fault is intermittent or persistent, but it does not fix the hardware issue. A continuity check of the sensor B3/10 wiring and connectors is needed to properly diagnose and resolve the fault.

Repair costs vary depending on the root cause identified during diagnosis. If the fix involves simply reseating a connector or cleaning the sensor lens, labor costs may be the primary expense, typically in the range of $75 to $150 depending on your area. A turbidity sensor replacement will add parts cost, generally putting the total repair in the $100 to $250 range. Control board replacement is the most expensive scenario and can bring total costs to $200 to $450 or more depending on the specific model.

Yes, the dishwasher is designed to continue operating when F88 is active, falling back to default program settings instead of sensor-driven cycles. Your dishes will still be washed, but the machine will not automatically adjust water usage, temperature, or cycle length based on load conditions. It is safe to keep using the dishwasher in the short term, but the underlying fault should be repaired to restore full functionality and efficiency.

Start by checking all wiring connections between the turbidity sensor B3/10 and the electronic control board, looking for loose, corroded, or broken connector pins. Perform a continuity check on the wiring harness to rule out any breaks in the circuit. If the wiring is intact, clean the optical lens of the turbidity sensor to remove any grease or limescale buildup, and test the sensor for proper electrical response. If the sensor has failed, it will need to be replaced, and in rare cases the control board may also be at fault.