What does SUD code mean on an whirlpool duet washer?

SUD indicates that the unit is detecting either a lot of soap suds in the wash drum or there is a problem with the units water level pressure switch.

The first thing you should check though is the coin trap for debris. The trap is located behing the front lower panel. Three screws along the bottom front of the washer and the panel comes off. Behind the panel to the right is a cap that you remove to clean out the coin trap.

NOTE: Any water still remaining in the unit will come out when the cap is removed. Have lots of rags on hand. Clean out the chamber real good and if there was a lot of stuff in there go ahead and try another load. Sometimes all that is needed is a good cleaning to let the water flow freely out of the unit.

If that doesnt work then you need to remove the top of the unit. Three screws along the back and the top comes off. On the top rear of the right hand cabinet panel is a component that has a small hose going to it. That is the water level presure switch. Disconnect the hose and blow through it to make sure it is not obstructed. If the hose is ok then you need to order a new switch to replace it with.

This should get you going again.

Best, HelpU2DIY