Bosch Washer E03 Error — Drain Pump Filter Fix

What it means

Bosch washer E03 error indicates a drainage fault — the machine can't pump water out at the expected rate.
The most common cause is a blocked debris filter at the front bottom of the machine; coins, hair clips, and lint collect there over months and eventually block water flow entirely.

Affected Models

Bosch Serie 2 / Serie 4 / Serie 6 / Serie 8 washing machines
Bosch Logixx, Maxx, Classixx ranges (older naming)
Bosch WAW, WAT, WAY, WAQ model series
Bosch Varioperfect washers
Same codes appear on Siemens and Neff washers (shared platform)

Common Causes

Drain pump filter blocked with lint, coins, or hair
Drain hose kinked or installed too high
Drain pump impeller jammed by a small object
Discharge end of the drain hose blocked
Drain pump motor failed

How to Fix It

Empty the debris filter.

At the front bottom of the washer, find the small access panel.
Place a shallow tray underneath, unscrew the filter cap counter-clockwise, and pull the filter out.
Clean off lint, hair, coins, and any small objects.
Refit and tighten.
Check the drain hose.

Pull the machine out and check the corrugated drain hose at the back for kinks or crushed sections.
Make sure the discharge end isn't pushed deeper than 100 cm into the standpipe — siphoning issues otherwise.
Test for hose blockage.

Disconnect the drain hose at the standpipe and aim it into a low bucket.
Run a Drain cycle.
If water flows freely now, the household drain is blocked, not the washer.
Listen for the drain pump.

Start a Drain cycle and listen at the bottom of the machine.
You should hear a low hum — the pump motor running.
Silence means the pump isn't getting power or has failed.

When to Call a Professional

Cleaning the debris filter is owner territory — five minutes with a tray and a screwdriver.
Call a technician only if the filter is clean and the hose is clear but E03 persists, since the pump motor may have failed.

Frequently Asked Questions

How often should I clean the Bosch washer pump filter?

Bosch recommends cleaning the debris filter every 4 to 6 months — more often if you wash items that shed a lot (fluffy towels, pet bedding) or regularly find coins and small items in pockets.
If you've never cleaned it and your washer is more than a year old, doing it now will likely uncover surprising amounts of debris and lint.
A clean filter prevents not just E03 but also smells, mould growth on the filter, and pump strain.