UO Moderate Moderate DIY

Frigidaire Dishwasher UO — Vent fault

Frigidaire Dishwasher · Error code UO

What UO Means

The vent assembly used to release steam at the end of the cycle is not operating. The wax motor or the vent door is stuck.

Symptoms

  • UO at end of cycle
  • Cycle completes but with wet dishes due to no venting
  • Audible buzz from vent motor
  • Dripping condensation on cabinet face

Common Causes

1
Failed vent wax motor

Wax actuator no longer extends to open the vent flap.

2
Vent door stuck closed

Food debris or detergent buildup on the flap pivot.

3
Open wiring to the vent assembly

Harness pinched in the door.

4
Failed control board vent output

Triac or transistor on board no longer drives the actuator.

How to Fix It

  1. Remove the inner door panel to access the vent assembly.
  2. Clean the vent flap and pivot of any grease/film.
  3. Operate the vent flap by hand to confirm it moves freely.
  4. Measure resistance across the wax motor leads (typically a few hundred ohms; open = bad).
  5. Replace the vent assembly if the actuator is open or the door is broken.
  6. Replace the control board if a known-good vent still doesn't actuate.

Parts You May Need

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

Common replacement Frigidaire dishwasher vent assembly / vent fan View on Amazon→

More Frigidaire Dishwasher Codes

Cd Cd — Clean indicator CL CL — Close the door ER ER — General electronic control fault Hot Hot — Water inlet too hot HS HS — Heater sensor fault i10 i10 — Water Not Detected (Fill)

All Frigidaire codes → All dishwasher codes →

Verified against manufacturer documentation: frigidaire.com

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician.