Control panel unresponsive or displaying random errors; E15 is sometimes logged as a communication fault.

Safety first: Unplug the appliance before removing the top or control panel.

Step-by-step checks:

• 1. Power reset:
  • Unplug the machine for at least 5 minutes.
  • Plug it back in and test; transient faults may clear.
• 2. Inspect control connections:
  • Remove the top cover and control fascia.
  • Check ribbon cables and connectors between the display board and power module.
  • Reseat connectors and look for corrosion or burnt pins.
• 3. Check for moisture:
  • Look for signs of condensation or leaks near the control area.
  • Dry gently and correct any leak sources.
• 4. Replace faulty boards:
  • If the user interface is dead but the power module is supplying voltage, replace the UI board.
  • If the UI is fine but the machine does not respond correctly, the power module may need replacement.

When to call a technician: Board-level diagnosis and programming often require Siemens tools; professional service is advised.