Match the symptom, then work through the safe checks.
1. What best matches what you observe?
2. Complete only the checks that are safe for you.
Show stop conditions
- E02 returns after one breaker reset
- The control board area smells hot, shows discoloration, or a breaker trips
- Further troubleshooting requires relay, PCB, mains-voltage, or internal wiring tests
Likely causes
- A relay on the main control board is not switching or reporting as expected
- The control electronics detect an abnormal relay state during self-monitoring
- A load or connection associated with the affected relay is causing the board to report a relay fault
- The control board needs model-specific diagnosis after a one-time power reset fails
Quick checks, in order
Keep E02 separate from E01
Bosch's published table assigns E02 to a main-control-board relay fault. Do not diagnose it as the E01 heat-pump motor circuit code.
Reset power for 30 seconds
Switch the dishwasher off at the breaker for about 30 seconds, restore power, and retry once as Bosch instructs.
Note which function was starting
Record whether the error appears at startup, heating, circulation, draining, or another transition. That context can help qualified service narrow which board-controlled load is involved.
Do not bypass or test relays while energized
Relay and PCB diagnosis involves mains-voltage control electronics. Do not jumper contacts, remove board covers, or probe energized terminals as a user-level check.
Does E02 return after the Bosch 30-second reset during the same control transition?
Monitor a complete cycle. If E02 returns, record the stage rather than repeatedly resetting the control.
A persistent relay/control switching fault needs model-specific board and connected-load diagnosis.
Stop repeated cycling. Qualified diagnosis should determine whether the board relay, connected load, wiring, or feedback is responsible.
Stop and get qualified help when
- E02 returns after one breaker reset
- The control board area smells hot, shows discoloration, or a breaker trips
- Further troubleshooting requires relay, PCB, mains-voltage, or internal wiring tests
Official support and model manuals
Use the full model number from the rating label. The manufacturer manual is the deciding reference when codes differ by region or product family.
Frequently asked questions
What does Bosch dishwasher E02 mean?
Bosch lists E02 as a main control board relay fault/error.
Does E02 prove the entire control board must be replaced?
No. The code identifies a control-relay fault domain, but the exact model's connected load, wiring, feedback, and board still need diagnosis before replacement.
Why is E02 different from E01?
Bosch specifically assigns E01 to the heat-pump motor circuit at the main control board, while E02 is a broader main-control-board relay fault.