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5-10

HIGH VOLTAGE
CAPACITOR

Antenna

Gasket

Filament
Terminals

Chassis

Normal : Momentary indicates

several ohms, and
then gradually
returns to infinite.

Normal : 

∞

.

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. 

Measure the resistance.
(Multi-meter scale : R x 1000) 
• Terminal to termonal.

Measure the resistance.
(Multi-meter scale : R x 1000) 
• Terminal to case.

Measure the continuity (Forward).
(Multi-meter scale : R x 10000) 

Measure the continuity (Reverse).
(Multi-meter scale : R x 10000) 

Normal : 

∞

.

Abnormal : Continuity.

Normal : Continuity.
Abnormal : 

∞

.

HIGH VOLTAGE
DIODE

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

5-11

HEATER ELEMENT
(Wire leads removed)

FUSE
(Wire leads removed.)

Normal

Abnormal

0°c~Approx 150°C

Approx 150°C

OVEN THERMOSTAT
MAGNETRON
THERMOSTAT

Normal : 
• Grill heater

Approx. 40.7 

Ω

(at 20~30°C)

Normal : more than 0.5M 

Ω

Measure the resistance with 500V-100M

Ω

insulation resistance meter.

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

Check for continuity of the switch with a
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.

5-12

GRILL HEATER
(Wire leads removed)

SOLENOID

RECTIFIRE ASM:
VOLTAGE FOR
SOLENOID

CIRCULATION MOTOR
(Wire leads removed)

NOTE:
*(     ) = WIRE COLOR

Normal : COM-230V : Approx. 150 

Ω

COM-24V : Approx. 20 

Ω

Abnormal : Infinite or several ohm.

Normal : Approx. 200~300 

Ω

Abnormal : Infinite or several

ohm.

Normal : Approx. 134 

Ω

Abnormal : Infinite or several ohm.
DC : 24V

24V
(BN)

COM
(YL)

230V(BL)

AC 28V

DC 24V

INPUT

OUT PUT

BN

YL

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

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

5-13

RELAY 3,4 OF P.C.B
(Disconnect the 7 pin 
connector from P.C.B)
See Schematic Dagram on
page 9)

RELAY 2,3,4 OF P.C.B
(Wire leads removed.)
RY2 : Microwave
RY3 : Grill 
RY4 : Convection

MEMBRANE KEY

Check continuity between
switch terminals, by pressing an
appropriate pad on key board.
The contacts assignment of the
respective pads on the key
board is as shown left figures.

Cooking Start

OFF

CN2

1

3

5

7

Relay 3

Relay 4

Relay 3 Relay 4 Relay 2

1
2
3
4
5
6
7
8
9

10
11

1
2
3
4
5
6
7
8
9
10
11

Membrane

Panel

P.C.B

Cooking Start

OFF

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

SERVICED FOR ANY REASON.
MAKE SURE THE WIRE LEADS ARE CORRECT POSITION.
WHEN REMOVING THE WIRE LEAD FROM THE PARTS, BE SURE TO GRASP THE
CONNECTOR, NOT THE WIRES.