LG Fridge LMX25986ST 00 Service Manual PDF

The LG LMX25986ST 00 is a 25.8 cubic foot French Door refrigerator with InstaView Door-in-Door, linear compressor technology, smart cooling system, water and ice dispenser, and ENERGY STAR certification. This service manual provides comprehensive technical information for qualified service technicians, including disassembly procedures, component specifications, troubleshooting guides, and wiring diagrams for proper maintenance and repair.

1. Safety Precautions 2. Product Specifications 3. Component Identification 4. Disassembly Procedures 5. Electrical System 6. Refrigeration System 7. Control System 8. Troubleshooting Guide 9. Parts List 10. Wiring Diagrams 11. Service Codes

Safety Precautions

Before performing any service procedures, read and understand all safety warnings and precautions to prevent personal injury and equipment damage.

Hazard TypePrecaution
Electrical ShockDisconnect power before servicing. Use insulated tools.
RefrigerantWear protective gloves and goggles when handling refrigerant lines.
Sharp EdgesWear cut-resistant gloves when handling evaporator coils and metal parts.
Heavy ComponentsUse proper lifting techniques for compressor and condenser units.
Chemical ExposureAvoid contact with insulation materials and refrigerants.

Product Specifications

Component Identification

Key components and their locations for service access and replacement procedures.

ComponentLocationFunction
Linear CompressorBottom rearRefrigeration cycle operation
Main Control BoardTop rear panelSystem operation control
Evaporator Fan MotorFreezer compartmentAir circulation
Condenser Fan MotorBottom rearHeat dissipation
Temperature SensorsMultiple locationsTemperature monitoring
Water Inlet ValveBottom left rearWater supply control
Ice Maker AssemblyFreezer doorIce production and dispensing

Disassembly Procedures

Step-by-step instructions for accessing and replacing major components.

  1. Door Panel Removal: Remove hinge covers, disconnect wiring harnesses, lift door off hinges.
  2. Control Panel Access: Remove screws from top grille, disconnect display connectors.
  3. Evaporator Cover: Remove freezer interior panels, disconnect defrost heater and sensors.
  4. Compressor Access: Remove rear service panel, discharge refrigerant properly.
  5. Water System: Shut off water supply, disconnect lines from dispenser assembly.

WARNING! Always disconnect power and recover refrigerant before opening sealed system.

Electrical System

Electrical specifications and testing procedures for system components.

Refrigeration System

Refrigerant circuit specifications and service procedures.

ParameterSpecification
Refrigerant TypeR-600a (Isobutane)
Refrigerant Charge2.5 oz ± 0.2 oz
High Side Pressure150-200 PSIG
Low Side Pressure0-5 PSIG
Compressor OilPolyolester (POE) Oil
Evaporator Temperature-10°F to 10°F

Control System

Electronic control system operation and diagnostic procedures.

  1. Main Control Board: Processes sensor inputs and controls all functions
  2. User Interface: Touch controls and display panel operation
  3. Sensor Network: Multiple temperature sensors throughout compartments
  4. Communication: Board-to-board communication via serial data lines
  5. Error Reporting: Stores fault codes for diagnostic purposes

Troubleshooting Guide

Common symptoms, possible causes, and corrective actions.

SymptomPossible CauseCorrective Action
No coolingCompressor failure, control board issue, refrigerant leakCheck compressor operation, test control outputs, leak test system
Excessive frostDefrost system failure, door seal leak, sensor faultTest defrost components, check door alignment, replace sensors
Water leakageClogged drain, cracked water line, dispenser issueClear drain tube, inspect water connections, check dispenser valve
No ice productionWater supply issue, ice maker failure, control problemCheck water pressure, test ice maker components, verify control signals
Display errorsControl board failure, wiring issues, power supplyTest board voltages, check wiring continuity, verify power input

Parts List

Common replacement parts with part numbers and descriptions.

Wiring Diagrams

Complete electrical schematics for system troubleshooting and repair.

Main Power Circuit: AC input, main board power supply, compressor circuit

Control Circuit: Microprocessor, sensor inputs, display interface, communication lines

Defrost System: Defrost heater, defrost thermostat, control relays

Water System: Water valve, ice maker, dispenser switch circuits

Note: Refer to detailed wiring diagrams in PDF manual for complete schematics.

Service Codes

Error codes and their meanings for diagnostic purposes.

Error CodeDescriptionAction Required
ER-IFCommunication errorCheck wiring between boards
ER-FFFreezer sensor errorReplace freezer temperature sensor
ER-RFRefrigerator sensor errorReplace refrigerator temperature sensor
ER-DSDefrost sensor errorReplace defrost temperature sensor
ER-CFCondenser fan errorCheck condenser fan motor and wiring
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