What does IC 40 mean?
Freezer compartment temperature has risen above 32°F (0°C) threshold.
Common causes
- Power outage
- Door left ajar
- Failed compressor
- Sealed system leak
- Defrost timer stuck in defrost
Diagnostic & testing steps
- 1. Check freezer temperature with independent thermometer
- 2. Verify door is sealing properly
- 3. Listen for compressor running
- 4. Check condenser coils are clean
- 5. Inspect evaporator for frost pattern - uneven frost indicates sealed system issue
- 6. Check defrost timer or adaptive defrost board
Tools required
- Thermometer
- Multimeter
- Vacuum
OEM parts & part numbers
Compressor Start Relay, Defrost Timer
Part numbers: 4201460, 4200500
Safety warning
⚠️ Check food safety - discard items if above 40°F for more than 2 hours
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