Dishwasher shows E10 and does not heat water properly; sometimes intermittent.

Safety first: Disconnect power before accessing the base or control module.

E10 points to a control issue in the heating circuit rather than a simple open heater.

• Step 1 – Check for loose connections:
  • Access the base and locate the heater/heat pump connectors.
  • Inspect for discoloration, melting, or looseness.
  • Reseat connectors firmly.
• Step 2 – Harness inspection:
  • Trace the heater wiring from the pump to the control module.
  • Look for pinched, cut, or burnt wires.
• Step 3 – Control board inspection:
  • Remove the inner door panel to access the control module.
  • Inspect the board for burnt tracks or components near the heater relay/triac.
• Step 4 – Functional test:
  • After reseating connectors, run a hot cycle and monitor if heating resumes.
  • If E10 returns, the control board is likely defective.
• Step 5 – Replacement:
  • Replace the power module/control board with the correct Siemens part.
  • Transfer all connectors carefully, one at a time.

Because this involves mains-voltage switching components, board-level repair should be left to professionals; most users should replace the entire module.