The error code UO is short for ‘Vent Open’, but instead of ‘V’, ‘U’ is shown. This is because some of the symbols cannot be displayed.
This Error Code implies that there is an issue with its fan, valve or sensor.
When the cycle is switched to dry mode, the fan is opened. This stops the dishwasher from washing.
You will also notice water draining and sound of a few clicks, when this error is displayed on the screen.
First of all, you need to restart the machine, as it can fix the issue in some cases. Also make sure to run the diagnostics on your machine.
Related Guide: Fix Frigidaire Dishwasher Error Code I50
Inspecting the Fan, Valve and Sensor
Reboot the machine and analyze the fan. Take a look at its connections and make sure that it is cleaned properly. Otherwise, the damaged wires can prevent the transmission of the signals.
The valve and sensor are located at the back of the dishwasher, covered by a solenoid. Once you remove the rubber element, you will see the valve.
Also, the sensor will be located nearby. Make sure to clean both of these parts thoroughly. Put the parts back into their place and run the machine again.
If the issue still persists, then the fan probably needs replacement. However, there is one other solution to make the fan work. You will see a sensor named U1, located on circuit panel, at the back of the fan. You can replace this part in order to make the fan work.
Once you have tried all these methods and it still doesn’t work, then you need to call a professional.