Built-in dishwasher with the door open and racks pulled out

Generic photo: Castorly Stock · Pexels License

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.

Cross-checked ~60 min moderateBrands: All

Before you start

Breaker off before any resistance test
Live-voltage checks at the heater are caution steps

Diagnostic steps

Unlock all 5 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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