Freezer shows F7 and compressor does not start or stops shortly after starting

Safety first: Unplug the freezer. Capacitors and compressor terminals can hold charge; avoid touching bare terminals.

• Access compressor terminals: Remove the rear lower cover to expose the compressor and its start device (relay and overload protector).
• Inspect start relay and overload: Remove the plastic cover on the compressor terminals. Check for burnt smell, melted plastic, or loose connections.
• Test start relay: With a multimeter, check continuity across the relay terminals according to Hitachi specifications. Replace if open or showing signs of burning.
• Test overload protector: Check for continuity through the overload device. An open reading when cool indicates failure.
• Check compressor windings: Measure resistance between the compressor terminals (C, S, R). Infinite or shorted readings indicate a bad compressor.
• Replace start components: If the compressor windings are good, install a new Hitachi start relay and overload protector assembly.
• Control PCB: If the compressor and start components are good but F7 persists and no voltage is sent to the compressor, the main control PCB may be defective.

Note: Replacing a locked compressor requires specialized tools and refrigerant handling; contact a certified technician.