E9 displayed, high temperature alarm may be active, compressor may not run

Safety: Unplug the freezer. Work on compressor and inverter circuits only if you are competent with mains electrics.

• Check mains supply: Verify the wall socket voltage is within normal range using a multimeter. Avoid using long extension leads or multi-way adaptors.
• Inspect wiring: Remove the rear lower panel and inspect the harness between the main PCB, inverter (if fitted), and compressor. Look for burnt connectors or melted insulation.
• Test compressor windings: With power off and wires removed from the compressor, measure resistance between each pair of terminals. All three readings should be similar and not shorted to earth. If windings are shorted or open, the compressor is faulty.
• Check inverter module: On models with a separate inverter, inspect for burn marks or bulging components. Replacement is usually the only remedy if faulty.

Because E9 typically involves high-voltage and sealed-system components, diagnosis beyond basic visual checks should be carried out by a qualified refrigeration engineer.