The LG Model LFX31925ST/00 is a 31.1 cubic foot French Door Refrigerator with Ice & Water Dispenser, featuring Linear Cooling technology, Door Cooling+, Smart Cooling Plus, and Smart Diagnosis. This service manual provides authorized technicians with essential information for installation, maintenance, troubleshooting, and repair. Below are key sections covering safety, specifications, component locations, disassembly, diagnostics, and parts lists.
Before servicing, read all safety warnings. Disconnect power before accessing internal components.
| Hazard | Precaution |
|---|---|
| Electrical Shock | Unplug unit or disconnect circuit breaker before servicing. Discharge capacitor. |
| Refrigerant | Use proper recovery equipment. Avoid open flames. Ventilate area. |
| Sharp Edges | Wear protective gloves when handling evaporator, condenser, or sheet metal. |
| Heavy Parts | Use proper lifting techniques or assistance for compressor, doors, and cabinet. |
| Moving Parts | Ensure all covers are secured before restoring power to prevent injury. |
Proper installation ensures optimal performance and safety.
WARNING! Do not install near heat sources. Ensure water line is leak-free.
Key components for service access.
| Component | Location | Function |
|---|---|---|
| Main Control Board | Top rear, behind access panel | Controls all refrigerator functions, receives sensor inputs |
| Compressor | Bottom rear, enclosed | Circulates refrigerant |
| Evaporator Fan Motor | Freezer compartment rear | Circulates cold air |
| Condenser Fan Motor | Bottom rear, near compressor | Cools condenser |
| Ice Maker Assembly | Freezer door (left side) | Produces and stores ice |
| Water Valve Assembly | Bottom rear, left side | Controls water flow to dispenser and ice maker |
| Temperature Sensors | Fresh Food & Freezer compartments | Monitor air temperature |
Step-by-step guide for accessing internal components.
CAUTION! Label all wires and connectors during disassembly. Handle door gaskets carefully to avoid tears.
Circuit diagrams and voltage specifications.
Tip: Use multimeter to verify voltages at connectors before replacing components.
Sealed system components and service ports.
WARNING! R-600a is flammable. No brazing on sealed system without purging with nitrogen. Follow EPA recovery guidelines.
Operation of electronic control system.
Main Control Board: Monitors sensors, controls compressor cycle, defrost, fans, and ice maker. Features Smart Diagnosis mode.
User Interface: Control panel on door includes temperature settings, filter reset, ice maker on/off, and lock controls.
Sensor Check: Fresh Food Sensor (10k ohm @ 77°F), Freezer Sensor (10k ohm @ 77°F), Defrost Sensor.
Entering Diagnostics: Press and hold "Ice Type" and "Filter Reset" buttons simultaneously for 3 seconds. Display will show test codes.
| Error Code | Description | Possible Cause | Corrective Action |
|---|---|---|---|
| FF / FR | Fresh Food Sensor Fault | Open/short circuit sensor, connector | Check sensor resistance (approx. 10kΩ at room temp). Replace if out of spec. |
| PF / PR | Power Failure | Power interruption > 2 hours | Reset by pressing any button. Check outlet power. |
| dH / dF | Defrost Heater Fault | Open heater, defrost thermostat, wiring | Check continuity of heater (20-30Ω) and defrost thermostat (closed when cold). |
| CE / CF | Communication Error | Wiring between display and main board | Check harness connections. Replace main control board or display board. |
| IE / IF | Ice Maker Assembly Fault | Ice maker motor, position sensor, obstruction | Run ice maker test mode. Check for jammed ice. Replace ice maker assembly. |
Service test modes for component verification.
CAUTION! Do not leave unit in forced test modes unattended for extended periods.
Reference for ordering replacement parts.
Exploded Views: Refer to diagrams Fig. 12-1 through 12-5 for cabinet, door, refrigeration system, and electrical part locations.
Ordering: Contact LG Parts at 1-800-243-0000 or visit www.lgpartsonline.com. Provide full model number LFX31925ST/00.