E4
What code E4 means on a Bosch dishwashers, what causes it, and which part to check first.
● SEVERITY: MEDIUM
Bosch E4 means: Water switch defective. The documented cause is: A service technician usually needs to diagnose and repair a water switch problem because accessing the sensor requires removing the dishwasher tub
What E4 means
Water switch defective
The display shows E4 and the machine stops until the fault is cleared.
What the technical documentation says
Causes documented in the technical source published by applianceaid.com
| DOCUMENTED CAUSE OR CHECK |
|---|
| A service technician usually needs to diagnose and repair a water switch problem because accessing the sensor requires removing the dishwasher tub |
Replacement parts
Tools you'll need
Before you open anything
Unplug the machine and close the water tap before removing any panel. The heating element and the wash water can stay hot long after the cycle ends.
What to check, in order
From the quickest check to the one that needs a technician.
Find a specialist
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Frequently asked questions
What does E4 mean on a Bosch?
Water switch defective The documented cause is: A service technician usually needs to diagnose and repair a water switch problem because accessing the sensor requires removing the dishwasher tub
Can I fix E4 myself?
It depends on the part involved: A service technician usually needs to diagnose and repair a water switch problem because accessing the sensor requires removing the dishwasher tub Clearing a filter or straightening a hose is within reach of anyone; anything behind a panel means mains electricity and water together — that is a job for a technician.
Does Bosch use other codes on this appliance?
Yes: we document 14 other codes for Bosch on this dishwashers. They are listed at the bottom of this page, each with its own meaning.
Does the same code mean the same thing on other brands?
Often not. The same two characters can point to completely different faults depending on the manufacturer — always check the page for your own brand.