What does SY EF mean?
Evaporator fan motor circuit failure.
Common causes
- Failed fan motor
- Ice blocking fan
- Wiring issue
- Control board failure
Diagnostic & testing steps
- 1. Check for ice around fan
- 2. Test fan motor electrically
- 3. Apply 12VDC to test
- 4. Check control board output
Tools required
- Multimeter
- 12V power supply
OEM parts & part numbers
Evaporator Fan Motor
Part numbers: 242077702, 297279800
Safety warning
⚠️ Unplug before testing
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