16
R-2275
R-2285
COMPONENT TEST
TEST PROCEDURES (CONT'D)
PROCEDURE
LETTER
STEPS
OCCURANCE
CAUSE OR CORRECTION
1
The rated AC voltage is not present at
POWER terminal of CPU connector (CN-A)
Check supply voltage and oven power cord.
2
The rated AC voltage is present at primary
side of low voltage transformer.
Low voltage transformer or secondary circuit defective.
Check and repair.
3
Only pattern at "a" is broken.
*Insert jumper wire J1 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)
NOTE: At the time of these repairs, make a visual
inspection of the varistor for burning dam-
age and examine the transformer with
tester for the presence of layer short-
circuit (check primary coil resistance). If
any abnormal condition is detected, re-
place the defective parts.
CARRY OUT 4R CHECKS
Q
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 220~230 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.
DC. voltage indicated ............................... Defective relay.
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 and Blower motor
RY2
APPROX. 17.5V D.C.
Power transformer 1
RY3
APPROX. 17.5V D.C.
Power transformer 2
CARRY OUT 4R CHECKS
R
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 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.
Problem: POWER ON, indicator does not light up.
CARRY OUT 3D CHECKS
4. If incorrect readings are obtained, replace the defective switch.
5. CARRY OUT 4R CHECKS
S1
S2
2
3
P
TI
C31
D23
+
–
VRS1
(J9)
(J8)
OL, BM
POWER
7
5
3
1
D21
CN–A
a
c
b
d
