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16
R-2277
R-2287
R-2287
TEST PROCEDURES (CONT'D)
PROCEDURE
LETTER
COMPONENT TEST
O
SWITCH UNIT TEST
1. CARRY OUT 3D CHECKS.
2. Remove the switch unit from the control panel, referring to control panel removal.
3. To test the switches (SW1-SW5) on the switch unit, check between the terminals of the connector
2. Remove the switch unit from the control panel, referring to control panel removal.
3. To test the switches (SW1-SW5) on the switch unit, check between the terminals of the connector
CN-F as described in the following table by using ohmmeter when the switches are released and
depressed.
depressed.
Switches
Terminals
Released Depressed
SW1
F1 - F4
O.C.
S.C.
SW2
F1 - F5
O.C.
S.C.
SW3
F2 - F4
O.C.
S.C.
SW4
F2 - F5
O.C.
S.C.
SW5
F3 - F4
O.C.
S.C.
Q
PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING
BOARD(PWB) IS OPEN
BOARD(PWB) IS OPEN
To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary
on the PWB, this foil pattern acts as a fuse. If the foil pattern is open, follow the troubleshooting guide
given below for repair.
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
OCCURANCE
CAUSE OR CORRECTION
1
The rated AC voltage is not present at
Check supply voltage and oven power cord.
POWER terminal of CPU connector (CN-A)
2
The rated AC voltage is present at primary
Low voltage transformer or secondary circuit defective.
side of low voltage transformer.
Check and repair.
3
Only pattern at "a" is broken.
*Insert jumper wire J9 and solder.
(CARRY OUT 3D CHECKS BEFORE REPAIR)
4
Pattern at "a" and "b" are broken.
*Insert the coil RCILF2003YAZZ between "c" and "d".
(CARRY OUT 3D CHECKS BEFORE REPAIR)
O.C. : Open Circuit
S.C. : Short Circuit
P
RELAY TEST
CARRY OUT 3D CHECKS.
Remove the outer case and check voltage between Pin Nos. 5 and 7 of the connector (A) on the
control unit with an A.C. voltmeter. The meter should indicate 230 volts, if not check control unit
circuity.
control unit with an A.C. voltmeter. The meter should indicate 230 volts, if not check control unit
circuity.
RY1, RY2 and RY3 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.
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,Blower motor and Stirrer motor
RY2
APPROX. 17.5V D.C.
Power transformer 1
RY3
APPROX. 17.5V D.C.
Power transformer 2
CARRY OUT 4R CHECKS.
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