Freezer shows E5; compressor may not run or may shut off quickly after starting.

Safety first: Unplug the freezer. The compressor terminals carry mains voltage. Do not touch bare terminals.

• Check ventilation: Ensure at least the manufacturer-recommended clearance around the freezer (typically 5–10 cm at sides and back). Clean dust from the condenser coils and rear grille.
• Access compressor components: Remove the rear lower service panel to expose the compressor, start relay/PTC, and overload protector.
• Inspect relay and overload: Remove the plastic cover on the compressor terminals. Check the start relay/PTC for burn marks, rattling pieces inside, or melted plastic. Inspect the overload protector for discoloration.
• Test components: With a multimeter, check continuity of the overload protector (should be closed at room temperature). For the PTC relay, compare resistance to service specs; if it is open, shorted, or physically damaged, replace.
• Replace start device: Install a Hisense-compatible compressor start relay/PTC and overload if faulty. Ensure they are firmly seated on the compressor pins and the cover is reinstalled.
• Power up and monitor: Restore power and listen for the compressor starting smoothly. If E5 returns and the compressor hums then clicks off, the compressor itself may be failing.

A failing compressor or repeated tripping of the overload should be diagnosed by a professional refrigeration technician.