LG Electronics GR-P257/L257 Oscillation circuit, Reset circuit, GR-P227/L227/P257/L257

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EXPLATION FOR MICOM CIRCUIT

1-2. Oscillation circuit

The oscillation circuit generates a basic clock signal for synchronization and time calculation related to the transmission of data and calculations made by the MICOM (IC1). The oscillator (OSC1) must always be replaced with an exact replacement part. If this specification is changed, the change will affect the time calculations of the MICOM and it might not work at all.

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

1-3. Reset circuit

The RESET circuit allows various parts of the MICOM, such as RAM, defrosting, etc., to be restarted from the initial state when power is interrupted or restored. A LOW signal applied to the reset terminal for 10 ms causes the MICOM to reset itself. During normal operation, the voltage at the reset terminal is 5 Vdc. If the reset fails, the MICOM will not operate.

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

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Contents Refrigerator Contents Page Front View SpecificationsRef No. GR-L227 Ref No. GR-P257 Ref No. GR-L257 Freezer Refrigerator compartment compartment Parts IdentificationRef No. GR-P227/GR-P257EXTERNAL Filter Parts Identification Parts Identification How to Adjust Door Height of Refrigerator HOW to Install RefrigeratorClass Shape and Spec Nomenclature How to Install Water PipeBefore Installation Single Lever Type Faucet general Connection of Pipe Connector a and BTwo Hands Type Faucet General TypeOutternal Filter Filter Fixation When customer uses bottled waterFilter Cleaning Replacement of water filter After installing water filterConfirm the amount of water supplied to the icemaker How to Control the Amount of Water Supplied to IcemakerDisplay Power saving Mode Door Alarm Buzzer Mute ModeMicom Function Monitor PanelDescription of Function Exhibition ModeLCD Back Light Control Outside temperature display functionLock function display button lock Filter condition display functionDispenser use selection When ice maker does not operate smoothlyAutomatic ice maker Express FreezerControl of variable type of freezing room fan Super freezingMiracle Zone function Control of M/C room fan motor Door opening alarmDoors of freezing Or home barSequential operation of built-in product Failure Diagnosis Function Test Function Mode Operation Contents RemarksFunction of dispenser and water dispenser built-in Test Mode 1 Status LCD Test Mode 2 Status LCDExplation for Micom Circuit Power circuitExplanation for PWB circuit GR-P227/L227GR-P227/L227/P257/L257 Reset circuitOscillation circuit Load Driving Circuit Load/dispenser operation, door opening circuitDispenser operation circuit Lever Switch sensing circuit Measuring partDoor opening sensing circuit Short Open Temperature sensing circuitSeparation Connection Status Application Standard Switch entry circuitOption designation circuit model separation function 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 Icemaking Mode Harvest ModeFill/Park Position Water supply amount TableDefect diagnosis function Stage Items Indicator RemarksCircuit Trouble Diagnosis Trouble ShootingNot 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 Power FaultsProblems Causes Checks Measures Remarks Problems Causes Checks MeasuresTemperature Cooling Disconnected from the motor Refer to fan motor disassembly Measures Remarks Problems CausesDefrosting failure 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 Micom Problems Symptom Causes Checks Measures RemarksDriving circuits Motor damper Replace door switch Trouble Diagnosis Items Unit Standards Purposes Remarks Cooling Cycle Heavy RepairSummary Of Heavy Repair Process Contents ToolsItems Precautions Precautions During Heavy RepairWhen replacing a compressor When replacing a drierPractical Work For Heavy Repair Inserting a capillary tubeVacuum Sequence Pipe ConnectionCharging sequence Calculation of amount of refrigerant charged12-0mm Standard Regulations For Heavy RepairEurope & CIS / America Brazing Reference DrawingsAsia / Middle-East Africa Explain the principles of temperature change Problems Checks and MeasuresSound depends on the installation location Explain general principles of soundsExplain the flow of refrigerant Explain the procedure and principles of ice maker operationExplain the characteriistics of moving parts Explain the principles of water supplied to dispenserMeasures for Symptoms on Temperature Odor and Frost Check the temperature control button and set at strongExplain the basic principles of food odor Explain the basic principles of frost formationOthers Remove a freezer door HOW to Disassemble and AssembleHandle InsertTubeLineColletClip Assembly COVER, Dispenser Exploded View Optional part Ref No. GR-P227/GR-P257Ref No. GR-L227/GR-L257 Freezer Compartment Optional part Refrigerator CompartmentMachine Compartment ICE & Water Part Dispenser Part No JD8999A