Frigidaire Dishwasher Error i20: Drain Error

The Logic Verdict

I watched a Frigidaire Gallery owner clear a stubborn i20 by vacuuming the pressure-switch port from inside the tub. Instead of yanking the dishwasher, he used a bent drinking straw to suck debris straight out of the tiny hole that feeds the switch. Try the same straw-and-water trick before ordering parts or pulling the machine.

What It Means

i20 pops when the control sees backpressure in the drain/level circuit. On these models the internal pressure sensor sits behind the left wall, but it’s fed by a pinhole in the sump basin. If that passage clogs, the sensor never sees the right water column and the board assumes a drain failure even though the pump is fine.

Common Causes

• Food sludge blocking the small sump port that routes water to the pressure switch (exactly what the video shows).
• Filter screens installed incorrectly, letting seeds or pasta fall below the mesh and into the sensor tube.
• A pressure sensor that’s actually damaged after repeat clogs (replace only if cleaning doesn’t reset the code).

Step-by-Step Fix

1. Cut power and unload the bottom rack. Trip the breaker or unplug the dishwasher so you can safely reach the sump.
2. Remove the filter assembly. Twist the inner fine screen counter-clockwise, lift it out, then pull the outer filter cup to expose the sump floor.
3. Fill the sump above the sensor port. Pour a cup or two of water into the well so the small hole (left of the main drain opening) sits under water.
4. Use a flexible straw to vacuum debris. Bend a cheap drinking straw, insert it into the tiny hole, and gently suck while plugging the outer end with your tongue. The loose fit pulls water and gunk up past the straw; spit the sludge into the sink.
5. Flush the passage. Blow lightly back through the straw to push clean water down the tube, then repeat the suck/flush cycle until no grit comes out.
6. Clean and reinstall the filters. Brush both screens, confirm there are no tears, drop them back in, and twist the inner screen until it locks with the arrow.
7. Run a rinse cycle. Restore power and run a quick cycle to verify the i20 clears without stopping mid-run.

Parts & Tools

• Frigidaire 154762601 pressure/turbidity sensor

Watch the Fix