LG Electronics LRMM1430SW, LRMM1430SB manual

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(3)CHECKOUT PROCEDURES FOR CIRCUIT BOARD The following symptoms indicate a defective circuit board.

(1)Check the input current. If the input current is more than 20A, check the magnetron and wiring. If the input current is less than 0.5 A, there is no input to the inverter.

(2)The start function fails to operate but the interlock switches, the door sensing and the relay check good.

(3)The unit with a normal relay continuously operates.

(4)The buzzer does not sound or continues to sound.

(5)Some segments of one or more digits do not light up, or they continue to light up, or segments light when they should not.

(6)Wrong figures appear.

(7)The figures of all digits flicker.

(8)Some of the indicators do no light up.

(9)The clock does not keep time properly.

NOTE: A MICROWAVE ENERGY LEAKAGE TEST MUST ALWAYS BE PERFORMED WHEN THE UNIT IS SERVICED FOR ANY REASON.

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Contents Microwave Oven Page Model LRMM1430SW LRMM1430SB Adjust the Latch and Switch Closings Adjustment ProceduresCheck the Door Latch and Switch Closings Test the Latch and Switch SequencePage General Precautions in USE Precautions on InstallationFeatures and Specifications Trial OperationSpecifications Switch ChartOverall Circuit Diagram A. Schematic Diagram Matrix Circuit for Touch KEY Board Operating Procedures A. Control Panel Display Window ClockKitchen Timer Easy USE Chart ClockHI-POWER Cooking MULTI-STAGE CookingMeasuring Microwave Energy Leakage Procedure for Measuring Microwave Energy LeakageEquipment Measurement with the OUT Case RemovedMeasurement with a Fully Assembled Oven Record Keeping and Notification After MeasurementDisassembly Instructions Important NotesWire Removing Control Circuit Board FigureAIR Guide Removal Figure Magnetron Removal Removing the Turntable MotorInterlock Mechanism FAN Motor Assembly RemovalInterlock System Monitor Switch Test Primary Interlock Switch TestSecondary Interlock Switch Test Components Test Procedure ResultsInverter Test and Checkout PROCEDURES, and TroubleshootingTest Procedures Components MagnetronSensor Correct PositionTurntable Motor RelayFAN Motor Problems Causes Checkout ProceduresCheckout Procedures for Fuse Blowing Problem B Checkout Procedures for RelayProblem a YES GoodPage Trouble Shooting Condition Cause RemedyResult ConditionCheck Check Result PCBCondition Check Result Cause RemedyNo microwave oscillation Exploded View Door Parts Controller Parts Oven Cavity Parts Latch Board Parts Oven Interior Parts Base Plate Parts Replacement Parts List For Model LRMM1430SBScrew TAPPING,PAN Head For Model LRMM1430SW WTT022 1TTL0402422 Schematic Diagram of P.C.B Printed Circuit Board B. Parts List LOC Description Specification SVC Alter RY1 May