Bosch Dishwasher Error Code E02 — Heater Relay Fault
What this means
The E02 error indicates a fault with the heater relay located on the main control board. This prevents the dishwasher from heating water to the correct temperature for washing and sanitizing. It can also be triggered by a faulty temperature sensor or thermistor providing incorrect readings to the board.
Alternate codes: E2
Step-by-step fix
3 stepsPower cycle the dishwasher
Turn off the circuit breaker for 5 minutes, then restore power and run a test cycle.
A temporary glitch in the relay can sometimes be cleared with a full power reset.
Check the temperature sensor
If the error returns, unplug the dishwasher and use a multimeter to test the thermistor resistance. At room temperature it should read approximately 50,000 ohms.
A reading far outside this range indicates a faulty sensor rather than a relay issue.
Replace the control board
If the thermistor tests fine, the heater relay on the control board has failed and the board needs replacement.
Note your exact model number before ordering a replacement board.
When to call a professional
Control board replacement involves accessing internal electronics and should be done by a qualified technician.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
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