Dishwasher Error Code: What They Mean and How to Fix Them

When your dishwasher flashes a strange code like dishwasher error code E1, F2, or UO, it’s not trying to be mysterious—it’s telling you something’s wrong. This isn’t a glitch you can ignore. These codes are diagnostic signals built into modern appliances to point you toward the real issue, whether it’s a clogged filter, a faulty pump, or a sensor that’s gone haywire. A dishwasher error code is your first clue, not the end of the line. Most people panic and call a repair technician right away, but half the time, the fix is simple—and you can do it yourself.

These codes relate directly to key parts of your dishwasher: the water inlet valve, controls the flow of water into the machine and often triggers error codes if it’s blocked or leaking, the drain pump, removes dirty water and can fail if food debris clogs it, or the control board, the brain of the dishwasher that interprets sensor data and displays error codes. If your dishwasher won’t start, it’s usually because the control board detected a problem with one of these components. And yes, different brands use different codes—Bosch’s E1 means something different than Whirlpool’s F2—but the underlying problems are often the same: water not flowing, water not draining, or sensors not reading right.

Before you assume the worst, check the basics. Is the door really latched? A loose seal can trigger a safety code. Is the filter clean? A clogged filter is the #1 reason for drainage errors. Did you overload the rack and block the spray arm? That can throw off water pressure sensors. These aren’t complicated fixes. Most error codes appear because of simple, preventable issues. You don’t need special tools—just a screwdriver, a towel, and five minutes. And if you’ve tried all that and the code keeps coming back? Then it’s time to look at the pump or the control board. But even then, replacing a pump is often cheaper than buying a whole new dishwasher.

What you’ll find below are real fixes for real error codes—no fluff, no theory, just what works. We’ve pulled together guides from people who’ve been there: the E1 that turned out to be a kinked hose, the F2 caused by a broken float switch, the UO that meant the vent wasn’t sealing right. These aren’t hypotheticals. These are fixes that saved people hundreds of dollars. Whether you’re dealing with a Bosch, a Siemens, a Samsung, or a GE, the patterns repeat. You’re not alone. And you don’t need to replace your dishwasher just because it’s showing a code. Sometimes, it just needs a little nudge.