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MICROWAVE OVEN

BEFORE SERVICING THE UNIT, READ THE
SAFETY PRECAUTIONS IN THIS MANUAL.

5-9

HIGH VOLTAGE
CAPACITOR

HIGH VOLTAGE
DIODE

NOTE :
Some inexpensive meters
may indicate infinite
resistance in both direction.

Measure the resistance.
(Ohm-meter scale: Rx1000)
• Terminal to terminal.

Measure the resistance.
(Ohm-meter scale: Rx1000)
• Terminal to case.

Measure the continuity (Forward).
(Ohm-meter scale: Rx10000)

Measure the continuity (Reverse).
(Ohm-meter scale: Rx10000)

Normal: Momentarily indicates

several ohms, and then
gradually returns to 
infinite.

Normal: ∞

Normal: Continuity.
Abnormal: ∞

Normal: ∞
Abnormal: Continuity.

NOTE: When testing the magnetron, be sure to install the magnetron gasket

in the correct position and be sure that the gasket is in good condition.

Antenna

Gasket

Chassis

Filament

5-10

FUSE

HEATER ELEMENT
(Wire leads removed.)

GRILL THERMOSTAT

OVEN THERMOSTAT
MAGNETRON
THERMOSTAT

Check for continuity of the fuse with an
multi-meter.

NOTE: If the fuse is blown, check the primary, the secondary, and the monitor
switches, H.V.D. and H.V.C. before replacing the fuse.
If the fuse is blown by improper switch operation replace the defective switch
and the fuse at the same time. Replace just the fuse if the switches operate
normally.

NOTE: Make sure heater is fully cooled when tested.

Measure the resistance.
(Multi-meter scale: Rx1)

Normal:
*Grill heater

Approx. 50 Ω
(at 20 ~ 30°C)

Normal: more than 200 MΩ

Normal               Abnormal

Measure the resistance with 500V-100M ohm
insulation resistance meter.

0°C~Approx.90°C   Approx.90°C

0°C~Approx.145°C Approx.145°C

5-11

TIMER MOTOR

(Wire leads removed)

FAN MOTOR
(Wire leads removed)

TURNTABLE
MOTOR
(Wire leads removed)

Check for continuity of timer motor with an
ohm-meter.
(Remove wire leads from timer motor)

Measure the resistance.
(Ohm-meter scale: R x 1)

Measure the resistance.
(Ohm-meter scale: R x 1000)

Normal: 

Abnormal: ∞ or several Ω

Normal: Approx. 100~200 Ω
Abnormal: ∞ or several Ω

NOTE : • A MICROWAVE LEAKAGE TEST MUST ALWAYS BE PERFORMED WHEN THE UNIT IS

SERVICED FOR ANY REASON.

• MAKE SURE THE WIRE LEADS ARE IN THE CORRECT POSITION.
• WHEN REMOVING THE WIRE LEADS FROM THE PARTS, BE SURE TO GRASP THE

CONNECTOR, NOT THE WIRES.

A

B

C

Turn On      Turn Off

A

B

Grill Switch

Microwave Switch

Approx. 22 KΩ

Note : A is timer ON, OFF        

switch.
B is power supply
terminal of the timer
motor.

A ~ B           A ~ C

30 ~ 50 Ω 300~500 Ω

A

B