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5-10

H.V. FUSE
MAIN FUSE
MONITOR FUSE

HEATER ELEMENT
(Wire leads removed.)

GRILL THERMOSTAT

OVEN THERMOSTAT
MAGNETRON
THERMOSTAT

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

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

NOTE: Make sure heater is fully cooled when tested.

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

Normal: 

●

Grill heater

Approx 38 

Ω

(at 20~30°C)

Normal: more than 0.5M 

Ω

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.

Normal

Abnormal

0°C~Approx 90°C

Approx 90°C

0°C~Approx 150°C

Approx 150°C

Cooking Start

OFF

Cooking Start

OFF

Normal : Approx. 150 ohm

abnormal : 

∞

or 

several ohms.

Normal : Approx. 10~20 K

Ω

abnormal : 

∞

or several 

ohms.

5-11

RELAY OF P.C.B.
(Disconnect the 5 pin
connector from P.C.B.)

RELAY 2 AND RELAY 3 
OF P.C.B.
(Wire leads removed.)
Note: Relay
Relay 1: Fan motor

Turntable motor
Oven lamp

Relay 2: Microwave
Relay 3: Grill

FAN MOTOR
(Wire leads removed)

TURNTABLE
MOTOR
(Wire leads removed)

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

Measure the resistance.
(Multi-meter scale : Rx 1000)

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.

5

3

1

CN 2

Relay 1

Relay 2

Relay 3

5-12

WHEN YOU GET A COMPLAINT FROM YOUR CUSTOMER, EVALUATE THE COMPLAINT CAREFULLY. 
IF THE FOLLOWING SYMPTOMS APPLY, PLEASE EDUCATE THE CUSTOMER IN THE PROPER USE OF
THE MICROWAVE OVEN. THIS CAN ELIMINATE AN UNNECESSARY SERVICE CALL.

1. Check grounding before checking for trouble.
2. Be careful of the high voltage circuit.
3. Discharge the high voltage capacitor. (See page 2-1)
4. When checking the continuity of the switches or of the high voltage transformer, disconnect one lead

wire from these parts and then check continuity with the AC plug removed. To do otherwise may result
in a false reading or damage to your meter.

5. Do not touch any part of the circuitry on the digital programmer circuit since static electric discharge

may damage this control panel.
Always touch yourself ground while working on this panel to discharge any static charge built up in your
body.

Microwave oven 

does not work.

Inserting many plug into one
plug outlet and using 
them at the same time 
(causes overloading)

Microwave oven plug is not
inserted tightly.

Output power is too low.

Low AC input voltage.

Food temperature is too low.

Using metallic ware and
allowing it to touch the oven
wall.

Sparks occuring.

Inconsistent intensity of
microwave by their charac-
teristics.

Uneven cooking.

Ceramic ware trimed in gold
or silver powder is used.

Avoid using other electrical
appliances when you use the
microwave oven.

Insert microwave oven plug
securely.

Use the microwave oven at
adequate line voltage.

This may not be a defect.
It is possible that the food
should be cooked for a
longer time period.

Do not use metallic ware for
cooking except where noted
in the cooking guide.

1. Wrap the thinner part with

aluminum foil.

2. Use plastic wrap or with a

lid.

3. Stir once or twice while

cooking soup, cocoa or
milk, etc.

Do not use any type of cook-
ware with metallic triming.

5-13

1. Incomplete segments.

• Segment missing.
• Partial segment missing.
• Digit flickering (NOTE:Slight flickering is normal.)

2. Colon does not turn on or blink.
3. A distinct change in the brightness of one more numbers in display.
4. One or more digits in the display are not lighting.
5. Display indicates a number different from one touched, for example, key in 5 and 3 appear in the display.
6. Specific numbers (for example 7 or 9) will not display when key pad is touched.
7. Display does not count down with time blinking or up with clock operation.
8. Display obviously jumps in time while counting down.
9. Display counts down too fast while cooing.
10. Each indicator light does not turn on after setting cooking cycle.
11. Display time of day does not reappear when cooking is finished.
12. Beep sound is not heard when correct key is touched.

1. No input can be

programmed.

Certainly.

No certainly.

Defective PCB
assembly.

Loose connec-
tion.

Replace PCB
assembly.

Connect them
tightly.

Check the conn-
ection between
membrane key
assembly and
PCB assembly.

2. Some inputs

cannot be pro-
grammed

3. Display shows a

number or figure
different from one
touched,

4. Random pro-

gramming when
touching other
pads.

5. Display is fixed

some figure and
can not be
accepted any
input.

Everything works
as specified.

Still have trouble.

Defective key
membrane assem-
bly.

Defective PCB
assembly.

Replace key mem-
brane assembly.

Replace PCB
assembly.

Replace key
membrane
assembly and
check operation.