Bosch dishwasher — Error Code E09

What it means

The E09 error on your Bosch unit signals a breakdown within the heating system. Unlike older machines, Bosch models forgo a visible heating element in the basin, opting instead for a flow-through heater built directly into the heat pump assembly. When the control board senses an open circuit, unusual resistance, or the water isn't warming up during a cycle, it displays E09. Because the heater is fused to the pump housing, you must replace the whole heat pump unit if the heater fails. In rarer cases, this fault stems from a scorched wiring harness connector or a faulty relay on the control module.

Likely Causes

1. 1
   Faulty Heat Pump Assembly

   The internal heating component within the pump has burned out, resulting in an open circuit. This is the primary reason for the E09 fault.
2. 2
   Damaged Wiring Harness or Connectors

   Wire connectors at the pump terminals can melt or lose their connection over time, severing the path between the control board and the heater.
3. 3
   Main Control Board Failure

   The relay on the main control module responsible for the heater may have burned out, preventing power from reaching the heat pump.

How to clear / reset

You can momentarily clear the E09 alert by performing a hard reset: hold the Start button for 3 to 5 seconds until the display shows '0:01' or '0:00', then power down. Alternatively, cut power via the circuit breaker for 5 minutes. Be aware that because E09 identifies a genuine hardware issue—specifically an open electrical circuit—the code will reappear as soon as the control board tries to activate the heater. The only permanent fix is to identify and replace the defective component.

Common replacement parts

FAQs