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5-18

Convection indicator lights
but oven does not go into
cook cycle when START key
is touched.

Temperature in the oven
cavity is lower or higher than
preset.

Defective circulation motor
wire ass'y.

Defective circulation
MOTOR.

Defective Relay 4, 8.

Defective relay 3, 4 or relay
8.

Defective convection heater
element.

Defective grill heater 
element.

Defective circulation Motor.

Defective or disconnected
thermistor.

Defective Solenoid

Defective Rectifire ASM

Defective DAMPER of
Airduct

Defective thermistor.

Test procedure thermistor.

Check and repair C-Motor wire
ass'y. (COM:YL, 24V:BN, 230V:BL)

Check and replace
C-Motor.

Test procedure relay 4, 8 of
P.C.B.

Test procedure relay 3, 4 or
relay 8 of P.C.B.

Test procedure convection
heater.

Test procedure grill heater.

Check the rotating of 
circulation fan.

Test or replace thermistor.

Test or Replace Solenoid

Check Diode(4pcs) or
Replace Rectifire ASM

Check or Repair Damper 
Pin and spring.

F1, F2, F5 is Fail display

Thermistor short (F1)

No sensing of 
thermistor (F2)

High initial temperature of
oven cavity. (F5)

Replace thermistor

Wait until low temperature of
oven cavity.

5-19

Grill indicator lights 
but oven does not go into
cook cycle when START key
is touched.

Temperature in the oven
cavity is lower or higher then
preset.

Defective relay 3 of P.C.B.

Open or loose wire 
connection to the above
components.

Check and repair wiring.

Test procedure relay 3 of
P.C.B.

Open or loose wire 
connection to P.C.B.

Check and repair wiring.

Defective relay 3 of P.C.B.

Defective grill heater 
element.

Test procedure grill heater.

Test procedure relay 3 of
P.C.B.

NOTE : • MAKE SURE THE WIRE LEADS CORRECT POSITION.

• WHEN REMOVING THE WIRE LEADS FROM THE PARTS, BE SURE TO GRASP THE CONNECTOR,

AND NOT THE WIRES.

• WHEN REMOVING THE MAGNETRON, BE SURE TO INSTALL THE MAGNETRON GASKET IN THE

CORRECT POSITION AND GOOD CONDITION.

• When you replace the magnetron, measure microwave

energy leakage before the out case is installed and
after all necessary components are replaced or
adjusted.
Special care should be taken in measuring the
following parts. (Shaded area of below Fig.)
— Around the magnetron
— The waveguide

• After all components, including the outer case, are fully

assembled, measure for microwave energy leakage
around the door viewing window, the exhaust opening
and air inlet openings.

• Microwave energy leakage must not exceed the values

prescribed below.

NOTES:
Leakage with the outer case removed - less than 
5 mW/cm

2

.

Leakage for a fully assembled oven (“Before the latch
switch (primary) is interrupted”) with the door in a slightly
opened position - less than 4 mW/cm

2

.

• Do not exceed meter full scale deflection.
• The test probe must be removed no faster than, 

1 inch/sec (2.5 cm/sec) along the shaded area,
otherwise a false reading may result.

• The test probe must be held with the grip portion of the

handle.
A false reading may result if the operator’s hand is
between the handle and the probe.

• When testing near a corner of the door, keep the probe

perpendicular to the surface making sure the probe
horizontally along the oven surface, this may possibly
cause probe damage.

• After adjustment and repair of any microwave energy

interruption or microwave energy blocking
device, record the measured values for future
reference. Also enter the information on the service
invoice.

• Should the microwave energy leakage not be more

than 4 mW/cm

2

after determining that all parts are in

good condition, functioning properly and genuine
replacement parts which are listed in this manual have
been used.

• At least once a year, have the electromagnetic energy

leakage monitor checked for calibration by its
manufacture.

5-2

• Microwave power output measurement is made with

the microwave oven supplied at its rated voltage and
operated at its maximum microwave power setting with
a load of (1000 ± 5)g potable water.

• The water is contained in a cylindrical borosilicate

glass vessel having a maximum material thickness of
3 mm and an outside diameter of approximately 190
mm.

• The oven and the empty vessel are at ambient

temperature prior to the start of the test.

• The initial temperature (±1) of the water is (10±2)°C. It

is measured immediately before the water is added to
the vessel. After addition of the water to the vessel, the
load is immediately placed on the center of the shelf
which is in the lowest position and the microwave
power switched on.

• The time T for the temperature of the water to rise by a

value 

∆

T of (10±2)°K is measured, where T is the time

in seconds and 

∆

T is the temperature rise. The initial

and final water temperatures are selected so that the
maximum difference between the final water
temperature and the ambient temperature is 5°K.

1) Disconnect power supply cord from the outlet.
2) Remove the screws from the rear and side section. 

The out case must be moved backward to the lifted off.

1) Remove the out case.
2) Disconnect two terminals from the noise filter assy

and remove one screw of the earth terminal.

CAUTION: DISCHARGE HIGH VOLTAGE

CAPACITOR BEFORE SERVICING
(refer to page 5)

1) Disconnect the leadwire from the PCB SUB ASM.

2) Remove the screws for the earth and securing  the

control panel.

3) Lift control panel assembly from the oven by the tab

unhooked.

• The microwave power output P in watts is calculated

from the following formula:

P =

is measured while the microwave generator is
operating at full power. Magnetron filament heat-up
time is not included. (about 2 sec.)

• The water is stirred, to equalize temperature

throughout the vessel, prior to measuring the final
water temperature.

• Stirring devices and measuring instruments are

selected in order to minimize addition or removal of
heat.

4) Remove three screws securing the PCB SUB ASM

from the control panel.

5) Remove the digitron window.

NOTE : Remove the leadwire and connector VERY

CAREFULLY. Be sure to grasp the connector
and not the wires.

5-3

Water Load

Turn Table

Control 

Panel

Spring

PCB 

Assembly

Button

Window

Button

Button

Release Lever

4187 

✸ 

(

∆

T

)

T