What to check yourself
Step 1. Open the supply valve fully
Check the valve under the sink is fully open, not part open. This is the answer surprisingly often, especially after somebody has worked under the sink or the machine has been moved.
Step 2. Clear the inlet hose and its filter
Turn the water off, unscrew the hose at the valve end, and rinse the mesh screen inside. Limescale and grit collect there and throttle the flow without stopping it completely.
Step 3. Check the hose is not kinked or crushed
Follow it from the machine to the valve. The usual pinch point is right behind the appliance where it has been pressed against the wall.
Step 4. Check the filter in the tub is not blocked
A badly blocked filter can leave the sump holding dirty water while the machine reads the level as wrong. Worth a minute while you are there, and it is the cheapest thing on this list.
What a technician will look at
Described so you know what you are paying for, not as steps to repeat.
Replace the inlet valve or the level sensor
If water flows freely and the level still reads low, either the valve is not opening fully or the sensor is misreading.
When to call a technician
After the valve, the hose and both filters. If the machine visibly fills and still reports a low level, the fault is the sensor and needs the panel off.
What the repair costs
| Repair | Part only | Fitted by a technician |
|---|---|---|
| Opening the valve, cleaning filters | - | Free |
| Inlet valve replacement | - | $150 to $300 |
| Level sensor replacement | - | $150 to $350 |
A new machine of the same class runs $500 to $1,500. Once a quote passes about a third of that on an older appliance, the repair stops making sense.
Codes people confuse this with
Questions people ask
- Bosch washing machines have an E18 too. Same thing?
- No, and this catches people out. On a Bosch washing machine E18 is a drain fault: the machine cannot get water out. On a dishwasher it is the opposite end of the cycle, not enough water coming in. Check which appliance you are looking at before following any advice.
Which machines this applies to
Applies to
All Bosch dishwashers. Machines with newer electronics show E3200 for the same fault.
Last checked
2026-08-04