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R-234 - 17
TEST PROCEDURES
Remove the outer case and check voltage between Pin No 5 of the 3 pin connector (A) and common
terminal of the relay (RY2) on the control unit with an A.C. voltmeter.
The meter should indicate rated voltage, if not check oven circuit.
terminal of the relay (RY2) on the control unit with an A.C. voltmeter.
The meter should indicate rated voltage, if not check oven circuit.
RY1 and RY2 Relay Test
These relays are operated by D.C. voltage
Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.
These relays are operated by D.C. voltage
Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.
DC. voltage indicated ............. Defective relay.
DC. voltage not indicated ....... Check diode which is connected to the relay coil. If diode is good,
DC. voltage not indicated ....... Check diode which is connected to the relay coil. If diode is good,
control unit is defective.
RELAY SYMBOL
OPERATIONAL VOLTAGE
CONNECTED COMPONENTS
RY1
Approx. 18.0V D.C.
Oven lamp / Turntable motor / Cooling fan motor
RY2
Approx. 7.0V D.C.
Power transformer
M
PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED
WIRING BOARD (PWB) IS OPEN
NOTE: *At the time of making these repairs,
make a visual inspection of the varistor.
Check for burned damage. If any ab-
normal condition is detected, replace
the defective parts.
Check for burned damage. If any ab-
normal condition is detected, replace
the defective parts.
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.
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.
STEPS
OCCURRENCE
CAUSE OR CORRECTION
1
The rated voltage is not applied between Pin
Check supply voltage and oven power cord.
No. 5 of the 3 pin connector (A) and the
common terminal of the relay RY2.
2
Only pattern at "a" is broken.
*Insert jumper wire J1 and solder.
3
Pattern at "a" and "b" are broken.
*Insert the coil RCILF2003YAZZ between "c" and "d".
L
RELAY TEST
K
TACT SWITCH TEST
1. Disconnect the oven from the power supply.
2. Discharge the high voltage capacitor.
3. Remove the control unit from the control panel.
4. By using an ohmmeter, check the tact switch operation.
5. When the tact switch is not depressed, an ohmmeter should indicate an open circuit. When the tact
2. Discharge the high voltage capacitor.
3. Remove the control unit from the control panel.
4. By using an ohmmeter, check the tact switch operation.
5. When the tact switch is not depressed, an ohmmeter should indicate an open circuit. When the tact
switch is depressed, an ohmmeter should indicate a short circuit. If improper operation is indicated,
the tact switch is probably defective and should be checked.
the tact switch is probably defective and should be checked.
RY2
R70
D70
1
5
(J1)
a
c
d
b
RY1
D71
D1
ZD70
VRS1
R1
CN - A
PROCEDURE
LETTER
COMPONENT TEST
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