Main PCB | LG Electronics GR-P227/L227, GR-P257/L257 manual

EXPLATION FOR MICOM CIRCUIT

1-13. Communication circuit and connection L/Wire between main PCB and display PCB

The following communication circuit is used for exchanging information between the main MICOM of the Main PCB and the dedicated MICOM of the LED (LCD) Display PCB.

A bi-directional lead wire assembly between the two boards is required for the display to function properly.

Poor communication occurs if a continuous information exchange fail to continue for more than 2 minutes between main MICOM of main PCB and LCD (LED) dedicated MICOM for LCD (LED) control of display PCB.

Main PCB

Main MICOM

L/Wire FD/H(4-wires)

DC 12V

GND

Transmission (error status)

Display PCB

LCD(LED) dedicated MICOM

Reception (notch status)

(1)GR-P227/L227/P257/L257

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LG Electronics GR-P227/L227, GR-P257/L257 service manual Main PCB

Contents

Refrigerator Contents Page Specifications Front View Ref No. GR-L227 Ref No. GR-P257 Ref No. GR-L257 Parts Identification Freezer Refrigerator compartment compartment Ref No. GR-P227/GR-P257EXTERNAL Filter Parts Identification Parts Identification HOW to Install Refrigerator How to Adjust Door Height of Refrigerator Before Installation How to Install Water PipeClass Shape and Spec Nomenclature Connection of Pipe Connector a and B Single Lever Type Faucet generalTwo Hands Type Faucet General Type Filter Cleaning When customer uses bottled waterOutternal Filter Filter Fixation After installing water filter Replacement of water filter How to Control the Amount of Water Supplied to Icemaker Confirm the amount of water supplied to the icemaker Door Alarm Buzzer Mute Mode Display Power saving ModeMicom Function Monitor Panel Exhibition Mode Description of Function Outside temperature display function LCD Back Light ControlLock function display button lock Filter condition display function When ice maker does not operate smoothly Dispenser use selectionAutomatic ice maker Express Freezer Miracle Zone function Super freezingControl of variable type of freezing room fan Door opening alarm Control of M/C room fan motorDoors of freezing Or home bar Sequential operation of built-in product Failure Diagnosis Function Mode Operation Contents Remarks Test Function Test Mode 1 Status LCD Test Mode 2 Status LCD Function of dispenser and water dispenser built-in Power circuit Explation for Micom CircuitExplanation for PWB circuit GR-P227/L227 Oscillation circuit Reset circuitGR-P227/L227/P257/L257 Load/dispenser operation, door opening circuit Load Driving Circuit Lever Switch sensing circuit Measuring part Dispenser operation circuit Door opening sensing circuit Temperature sensing circuit Short Open Option designation circuit model separation function Switch entry circuitSeparation Connection Status Application Standard Stepping motor operation circuit Fan motor driving circuit freezer, mechanical area +5 C +9F 33 k Ω 56 k Ω JCR1 Main PCB Sensor resistance characteristics table Miracle Zone Stepping Motor / Display Operation Principle Harvest Mode Icemaking ModeFill/Park Position Water supply amount Table Stage Items Indicator Remarks Defect diagnosis function Circuit Trouble Shooting Trouble Diagnosis Not performed Evaporator by heating as Refrigeration Refrigeration Residual Refrigeration No cooling air circulation Is weak Fan does not work Recess Sounds Compressor compartment operating sounds Bad soldering Bad rivet contact Short Structure Door foam Appearance Sag Faults PowerProblems Causes Checks Measures Remarks Problems Causes Checks Measures Temperature Cooling Disconnected from the motor Refer to fan motor disassembly Defrosting failure Problems CausesMeasures Remarks Remove the parts and replace it Icing Discharging port of cooling air Sound Click Contraction of evaporator Sources Sound Burping It happens when refrigerant expands Odor Problems Symptom Causes Checks Measures Remarks Micom Driving circuits Motor damper Replace door switch Trouble Diagnosis Cooling Cycle Heavy Repair Items Unit Standards Purposes Remarks Process Contents Tools Summary Of Heavy Repair Precautions During Heavy Repair Items Precautions When replacing a drier When replacing a compressorPractical Work For Heavy Repair Inserting a capillary tube Pipe Connection Vacuum SequenceCharging sequence Calculation of amount of refrigerant charged Standard Regulations For Heavy Repair 12-0mm Asia / Middle-East Africa Brazing Reference DrawingsEurope & CIS / America Problems Checks and Measures Explain the principles of temperature changeSound depends on the installation location Explain general principles of sounds Explain the procedure and principles of ice maker operation Explain the flow of refrigerantExplain the characteriistics of moving parts Explain the principles of water supplied to dispenser Measures for Symptoms on Temperature Check the temperature control button and set at strong Odor and FrostExplain the basic principles of food odor Explain the basic principles of frost formation Others HOW to Disassemble and Assemble Remove a freezer door Handle InsertTubeLineColletClip Assembly COVER, Dispenser Exploded View Ref No. GR-P227/GR-P257 Optional part Ref No. GR-L227/GR-L257 Freezer Compartment Refrigerator Compartment Optional part Machine Compartment ICE & Water Part Dispenser Part No JD8999A