Built-in dishwasher with the door open and racks pulled out
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Field pattern: Bosch dishwasher E09 / no heat (the heater is inside the circulation pump: check terminals and sensors before buying the assembly)

On most Bosch-built dishwashers the heater is built into the circulation pump housing (the 'heat pump'), so there is no visible element. E09 is tied to the heating circuit: the heater itself, its terminals, the temperature/flow sensing or the control's heater relay. The wrong turn is hunting for an element in the tub, or buying the heat pump assembly without measuring the heater and checking its connector for corrosion.

Cross-checked ~75 min advancedBrands: Bosch, Thermador, Gaggenau

Before you start

  • Shut off power at the breaker and water at the valve before removing the kick panel or tipping the unit
  • Heater circuit checks under power are live-voltage tests: insulated probes, one hand, dry floor
  • Bosch's own consumer guidance is to have E09 repaired by a technician

Diagnostic steps

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Field pattern: Bosch dishwasher E09 / no heat (the heater is inside the circulation pump: check terminals and sensors before buying the assembly) · OnCall Tech