F4
Belling
Door Switch / Door Sensor Fault
F4 displayed; interior light may not work and door alarm may behave erratically.
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Possible Causes
Failed mechanical door switch, Misaligned magnetic door sensor (on some models), Broken switch wiring, Faulty input on main PCB
How to Fix / Troubleshooting
Safety: Unplug the freezer before removing the door switch or frame trim.
Steps:
- 1. Test switch operation: Press the door switch plunger by hand. The interior light should turn on/off. If not, suspect a faulty switch or bulb/LED driver.
- 2. Inspect switch: Gently pry out the switch from the cabinet frame. Check for broken terminals or corrosion.
- 3. Electrical test: Use a multimeter to check continuity across the switch terminals while pressing and releasing the plunger. Replace the switch if it does not change state.
- 4. Wiring: Inspect the wiring from the switch to the PCB. Repair or replace if damaged.
- 5. PCB input: If the switch and wiring are good but F4 persists, the PCB input circuit may be faulty and require PCB replacement.
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Repair Difficulty
Easy
2/5
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