In Frigidaire dishwasher models, error code UO manifest by the wash tank filling system starting, then several (3-4) clicks are heard, and error code UO is displayed. If canceled, the dishwasher will drain water. However, upon the next switch on, the error appears again.
Error UO: description
The error code stands for ‘Vent Open’ but because letter V cannot be displayed, letter U appears. Before initiating repairs, reset the era by restarting the device. To do this, disconnect the device for 10-15 minutes and then switch it on again. For maximum accuracy, carry a self-diagnostic test by holding the Air Dry and Start buttons for 3 seconds. If the problem persists, the system will immediately report it.
The code UO simply a breakdown of the mainboard or the ventilation subunit. Experts and manufacturers advise users to replace these parts. However, repairs can still be carried.
1. Faulty wiring and lose connections
There are wires that stretch from the bottom of the door to the control module. Check its integrity and any fault in the wires that may prevent the transmission of signals. To repair them, clean the rusted ones, fasten the joints, solder, twist, and replace others as necessary.
2. Dirty valve or sensor
Clean the valve from residual soap and limescale. Also, clean the small optical sensor that tells the board about the position of the plunger. Remove plaque from this part using a lens solution and a nylon brush.
3. Broken ventilation subunit
The ventilation subunit may not be easily checked or repaired. The only solution could be replacing it with a new one. However, its lifespan and effectiveness can be improved through regular maintenance. This can be achieved by:
- making sure that the ventilation hole normally closes at the beginning of the cycle;
- accessing the assembly and remove the U1 element from the circuit board behind the valve;
- installing a new sensor that costs far less than the cost of a full set of a ventilation unit.
4. Problematic control module
The control module may be problematic due to electrical shots, corrosion, rusting, or damages caused by an unexpected power surge. To access it, unscrew the fasteners on the front of the dishwasher, remove the door panel, and the waterproof coating. Re-solder dysfunctional parts restore burned ones or if the damage is severe, replace them. In extreme cases, install a new module,