LG Electronics LRMM1430SB Test and Checkout PROCEDURES, and Troubleshooting, Inverter, Magnetron

Page 21

11. TEST AND CHECKOUT PROCEDURES, AND TROUBLESHOOTING

CAUTIONS

1.DISCONNECT THE POWER SUPPLY CORD FROM THE OUTLET WHENEVER REMOVING THE OUTER CASE FROM THE UNIT. PROCEED WITH THE TEST ONLY AFTER DISCHARGING THE HIGH VOLTAGE CAPACITOR AND REMOVING THE LEAD WIRES FROM THE INVERTER MODULE.

2.ALL OPERATIONAL CHECKS WITH MICROWAVE ENERGY MUST BE DONE WITH A LOAD (1 LITER OF WATER IN CONTAINER) IN THE OVEN.

A.TEST PROCEDURES

COMPONENTS

TEST PROCEDURE

RESULTS

INVERTER

(Lead wires removed)

CN702

Heat Sink

E701

120V AC

CN701	High Voltage
	Output to
	Magnetron
	CN703
	Control Signal
	In/Out

Note: Do not try to repair the inverter board, nor try to make any adjustments to the board.

Check wiring to the inverter:

1.Unplug the oven’s main power supply.

2.Visually inspect 4 connectors on the inverter board: CN701, CN702, CN703, E701 to see whether there are any signs of failure due to loose wires, bad crimping, sign of overheating, etc.

	MAGNETRON	1. Measure the resistance.
	(Lead wires removed)	1. Measure the resistance.	Normal: Less than 1 ohm
	(Lead wires removed)	(Ohm-meter scale: Rx1)


		• Filament terminal
		2. Measure the resistance.	Normal: Infinite
		(Ohm-meter scale: Rx1000)	Normal: Infinite
		(Ohm-meter scale: Rx1000)
		• Filament to chassis

-20-

Image 21

Contents Microwave Oven Page Model LRMM1430SW LRMM1430SB Check the Door Latch and Switch Closings Adjustment ProceduresAdjust the Latch and Switch Closings Test the Latch and Switch SequencePage Features and Specifications Precautions on InstallationGeneral Precautions in USE Trial OperationSwitch Chart SpecificationsOverall Circuit Diagram A. Schematic Diagram Matrix Circuit for Touch KEY Board Operating Procedures A. Control Panel Clock Display WindowHI-POWER Cooking Easy USE Chart ClockKitchen Timer MULTI-STAGE CookingEquipment Procedure for Measuring Microwave Energy LeakageMeasuring Microwave Energy Leakage Measurement with the OUT Case RemovedRecord Keeping and Notification After Measurement Measurement with a Fully Assembled OvenImportant Notes Disassembly InstructionsRemoving Control Circuit Board Figure WireAIR Guide Removal Figure Removing the Turntable Motor Magnetron RemovalFAN Motor Assembly Removal Interlock SystemInterlock Mechanism Secondary Interlock Switch Test Primary Interlock Switch TestMonitor Switch Test Components Test Procedure ResultsTest Procedures Components Test and Checkout PROCEDURES, and TroubleshootingInverter MagnetronCorrect Position SensorRelay FAN MotorTurntable Motor Checkout Procedures Checkout Procedures for Fuse BlowingProblems Causes Problem a Checkout Procedures for RelayProblem B YES GoodPage Condition Cause Remedy Trouble ShootingCondition CheckResult PCB Check ResultCause Remedy Condition Check ResultNo microwave oscillation Exploded View Door Parts Controller Parts Oven Cavity Parts Latch Board Parts Oven Interior Parts Base Plate Parts For Model LRMM1430SB Replacement Parts ListScrew 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