What does Er dH mean?
Defrost system not functioning. Evaporator defrost heater circuit failed.
Common causes
- Failed defrost heater
- Faulty defrost thermostat
- Main control board issue
- Wiring damage
Diagnostic & testing steps
- 1. Access evaporator (remove freezer rear panel)
- 2. Check for heavy frost on evaporator
- 3. Test defrost heater: 20-50 ohms
- 4. Test bi-metal thermostat: closed at room temp
- 5. Check defrost sensor resistance
Tools required
- Multimeter
- Phillips screwdriver
- Hair dryer
OEM parts & part numbers
Defrost Heater, Defrost Thermostat, Defrost Sensor
Part numbers: 5300JB1092A, 6615JB2002M
Safety warning
⚠️ Careful of sharp evaporator fins
Try DiagBuddy AI free — instant 30-second diagnostics for technicians.