Thermador · Dishwasher error code

E04Heater electronics fault

Single source High-voltage / caution

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Related diagnostic guides

Guide · Dishwasher

Bosch / Thermador / Gaggenau dishwashers: E-codes, resets and the stored-fault test program

Current BSH dishwashers show E-codes on the display; Bosch's own pages tie E24 to a drain problem and E15 to water in the base (leak protection). A reset is a power cycle or holding Start for a few seconds, which cancels the program and pumps out. Older models have a test program entered by holding two program buttons while switching on; it shows stored faults as numbers that add together (1, 2, 4, 8, 16), so a 3 means faults 1 and 2.

7 steps ~30 minmoderate

Guide · Dishwasher

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.

7 steps ~75 minadvanced

Guide · Dishwasher

Dishwasher not heating water

Confirm the supply water is hot first, then test the heater (or Bosch heat pump heater), the high-limit and the thermistor. If all test good, suspect the heater relay on the control.

5 steps ~60 minmoderate