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TEST PROCEDURES
PROCEDURE
LETTER
C
RELAY TEST
CARRY OUT 3D CHECKS.
Remove the outer case and check voltage between Pin Nos. 1 and 3 of the 4 pin connector (A) on
the control unit with an A.C. voltmeter.
The meter should indicate 230-240 volts, if not check oven circuit.
Relay Test
Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.
convection cooking operation or grill operation.
DC. voltage indicated .......... Defective relay.
DC. voltage not indicated .... Check diode which is connected to the relay coil. If diode is good,
RELAY SYMBOL
CARRY OUT 4R CHECKS.
D
PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING
BOARD (PWB) IS OPEN.
To protect the electronic circuits, this model is provided with a fine foil pattern added to the input circuit
on the PWB, this foil pattern acts as a fuse. If the foil pattern is open, follow the troubleshooting guide
given below for repair.
Problem: POWER ON, indicator does not light up.
CARRY OUT 3D CHECKS.
STEPS
1
2
3
4
NOTE: *At the time of these repairs, make a
CARRY OUT 4R CHECKS.
control unit is defective.
OPERATIONAL VOLTAGE
RY1
Approx. 24.0V D.C.
RY2
Approx. 18.0V D.C.
RY3
Approx. 18.0V D.C.
RY4
Approx. 18.0V D.C.
RY5
Approx. 24.0V D.C.
OCCURANCE
The rated AC voltage is not present at
Power terminal of CPU connector (CN-A).
The rated AC voltage is present at primary
side of low voltage transformer.
Only pattern at "a" is broken.
Pattern at "a" and "b" are broken.
visual inspection of the varistor for burn-
ing damage and examine the trans-
former with tester for the presence of
layer short circuit (check primary coil
resistance).
If any abnormal condition is detected,
replace the defective parts.
771M -
COMPONENT TEST
CONNECTED COMPONENTS
Oven lamp / Turntable motor
High voltage transformer
Grill heating element (Top grill)
Bottom heating element
Fan motor
CAUSE OR CORRECTION
Check supply voltage and oven power cord.
Low voltage transformer or secondary circuit defective.
Check and repair.
*Insert jumper wire J1 and solder.
(CARRY OUT 3D CHECKS BEFORE REPAIR)
*Insert the coil RCILF2003YAZZ between "c" and "d".
(CARRY OUT 3D CHECKS BEFORE REPAIR)
8
c
a
b
(J1)
d
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