The compressor does not start, there is a clicking noise from the rear, and the display shows 'F04' or a compressor fault indication.

Safety first: Unplug the refrigerator. Only work in the rear service area. Do not open the sealed refrigeration system.

Steps:

• 1. Listen and observe: After plugging in (for testing only), note if the compressor hums briefly then clicks off, or if it is completely silent while F04 appears.
• 2. Access compressor area: Unplug again. Remove the lower rear cover to expose the compressor, start device (PTC/overload) or inverter module, and main control board.
• 3. Check connections: Ensure the harness from the main control board to the compressor or inverter is firmly seated. Look for burnt connectors or melted plastic.
• 4. Inspect start device (non-inverter): If your V-ZUG model uses a PTC relay and overload protector, remove them from the compressor pins and inspect for rattling pieces or burn marks. Replace them as a set if suspect.
• 5. Inspect inverter module (inverter models): Look for LED status indicators (if present) and any visible damage. A burnt smell or cracked components indicate failure.
• 6. Basic electrical checks (advanced): With the unit unplugged, measure the compressor winding resistance between terminals; values should be stable and not open or shorted. Abnormal readings suggest compressor failure.
• 7. Replace faulty module: If the compressor windings test OK but the inverter or start relay is damaged, replace the module with the exact V-ZUG part number.
• 8. If compressor is defective: Compressor replacement requires specialized tools, refrigerant handling certification, and V-ZUG-approved procedures. Contact an authorized technician.

Warning: Never attempt to cut or open refrigerant lines yourself. This is hazardous and illegal in many regions.