Bosch Dishwasher Error Code E33 — What It Means & How to Fix It

What Does This Error Mean?

The E33 error on a Bosch dishwasher means the control board has detected that the water level inside the tub is too high before the wash even begins. This suggests water remained in the tub from a previous cycle that did not drain correctly, or water entered the tub when the machine was off. The dishwasher will not start a new cycle until the excess water is removed.

Affected Models

SHPM88Z75N
SHEM63W55N
SHPK7TL5UC
SHPM65Z55N
Bosch 300, 500, and 800 Series models

Common Causes

The previous cycle did not drain fully — the drain pump or filter is clogged
The drain hose is kinked or positioned too low, causing water to siphon back into the tub
The inlet water valve is not closing fully, allowing water to slowly drip in when the machine is idle
The pressure sensor is stuck in the 'water present' position due to a fault
The garbage disposal knockout plug was not removed during installation, blocking the drain

How to Fix It

Cancel any active program and allow the dishwasher to attempt to drain.

Press and hold Start for 3 seconds to cancel. The machine should then run the drain pump automatically.
Remove the bottom rack and pull out the filter assembly.

Clean the coarse filter and fine mesh filter under warm running water. A clogged filter prevents draining.
Check the drain hose at the back of the machine — it should form a high loop before connecting to the sink drain.

A low-hanging drain hose lets water siphon back in after the cycle ends. The hose loop should be at least 20 inches above the floor.
If connected to a garbage disposal, confirm the knockout plug was removed from the disposal inlet.

New disposals ship with a plastic plug in the dishwasher inlet — it must be knocked out before connecting the hose.
Restore power and run a rinse-and-hold program to test draining.

If E33 returns at the start of the cycle, the inlet valve or pressure sensor needs professional inspection.

When to Call a Professional

If cleaning the filter and checking the drain hose does not resolve E33, call a technician. The inlet valve, pressure sensor, or drain pump may need testing and replacement. A constantly leaking inlet valve will cause flooding if not repaired. Expect repair costs of $100–$240 depending on which part is faulty.

Frequently Asked Questions

Why does my Bosch dishwasher keep having standing water at the start of a cycle?

A small amount of water (about 1 inch) at the bottom of a Bosch dishwasher is actually normal. Bosch uses a condensation drying method that keeps water in the base of the sump. However, if water is clearly above the heating element or up to the filter level, the previous cycle did not drain properly. Check the filter and drain hose first.

What is the high-loop rule for a dishwasher drain hose?

The drain hose should loop up as high as possible under the counter — at least 20 inches from the floor — before connecting to the sink drain or disposal. This high loop prevents water from siphoning back into the dishwasher after the cycle ends. Without it, dirty water can flow back in and trigger the E33 error repeatedly.

Can a faulty water inlet valve cause E33 on a Bosch dishwasher?

Yes — if the inlet valve is not fully closing, water slowly drips into the tub even when the dishwasher is off. Over time (or even overnight), this can raise the water level enough to trigger E33 at the start of the next cycle. A technician can test the valve by measuring its electrical resistance with a multimeter.