Bosch Dishwashers error code
Main-control relay fault
E03 is another main control-board relay fault listed by Bosch.
Direct answer
E03 at a glance
- Meaning
- Main-control relay fault
- Urgency
- Service recommended
- First safe check
- Switch the dishwasher off.
- Model note
- Confirm the code and access instructions in the manual for your exact model.
Likely causes
Why E03 appears
- 01Temporary control fault
- 02Main-control relay fault
Safe diagnostic path
What to check, in order
- 01
Switch the dishwasher off.
- 02
Reset power at the breaker for 30 seconds.
- 03
Restore power and retry once.
- 04
Contact Bosch support if E03 returns.
Know when to stop
Don’t push past this point
Do not access internal electronics. Arrange service if the code returns.
Primary source
How this page was checked
The code meaning and manufacturer-specific guidance were checked against the linked support material on August 28, 2026. Confirm details against the manual for your exact model before removing panels or parts.
Read Bosch US: dishwasher error codes ↗Common follow-up questions
About Bosch code E03
What does E03 mean on a Bosch dishwashers?
E03 means “Main-control relay fault.” E03 is another main control-board relay fault listed by Bosch.
Can I clear E03 by resetting the appliance?
A reset may clear a temporary alert, but it does not correct the underlying condition. Start with the safe checks above and stop if the code returns. Do not access internal electronics. Arrange service if the code returns.
Does E03 mean the same thing on every Bosch model?
Not necessarily. Display codes can vary by model and product family, so confirm the meaning and access instructions in the manual for your exact model before removing covers or parts.
When should I stop troubleshooting E03?
Do not access internal electronics. Arrange service if the code returns.