E9 error displayed; ice build-up on evaporator; fan noise may increase or airflow is weak.

Safety first: Disconnect mains power before accessing the freezer evaporator or heater wiring.

Procedure:

• 1. Visual inspection: Remove freezer drawers and rear panel. Look for burnt insulation or melted plastic near the heater or wiring.
• 2. Test heater resistance: Disconnect heater leads and measure resistance. A very low resistance (near 0 Ω) or visible damage indicates a shorted heater that must be replaced.
• 3. Inspect wiring harness: Follow the heater and sensor wires. Look for spots where wires may have rubbed against metal and shorted. Repair with proper high-temperature wire and connectors.
• 4. Check defrost thermostat: If fitted, test the thermostat for proper operation (closed when cold, open when warm). A thermostat stuck closed can contribute to overheating.
• 5. Reset and test: After repairs, reassemble, restore power, and monitor for recurrence of E9. If the error returns with all components verified, the main PCB may be misreading current and require replacement.

Note: Use only Siemens-approved heater assemblies and high-temperature wiring in the evaporator area.