R-890SLM
a
7
0P
J
1S
A-
N
C
[15] O: RELAY TEST
CARRY OUT 3D CHECKS.
Remove the outer case and check voltage between Pin Nos. 5 and 7 of the 4 pin connector (E) 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, grill operation, convection operation or
combi 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 / Turntable motor
RY2
APPROX. 18.0V D.C.
High voltage transformer
RY3
APPROX. 24.0V D.C.
Grill (Top) heating element
RY4
APPROX. 24.0V D.C.
Bottom heating element
RY5
APPROX. 24.0V D.C.
Touch control transformer
RY6
APPROX. 24.0V D.C.
Fan motor
RY7
APPROX. 24.0V D.C.
Convection motor
CARRY OUT 4R CHECKS.
[16] P: 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
OCCURRENCE
CAUSE OR CORRECTION
1
The rated AC voltage is not present between Pin Nos.
5 and 7 of the 4-pin connector (E).
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 replace the touch control transformer or the
control unit.
3
Pattern at “a” is broken.
Replace the control unit.
(CARRY OUT 3D CHECKS BEFORE REPAIR)
NOTE: *At the time of these repairs, make a visual inspection of the varistor for burning
damage and examine the transformer with tester for the presence of layer short
circuit (check primary coil resistance).
If any abnormal condition is detected, replace the control unit.
CARRY OUT 4R CHECKS.
8 - 5
W
H
3-
7
W
H
3-
8
W
H
3-
10
W
H
3-
9
4
-
3
H
W
3
-
3
H
W
2
-
3
H
W
1
-
3
H
W
S
S
E
R
P
X
E
K
O
O
C
SW1
/
P
O
T
S
R
A
E
L
C
SW13
KITCHEN TIMER
/ CLOCK SET
SW14
L
L
I
R
G
SW6
I
B
N
O
C
SW4
T
R
A
T
S
SW15
O
F
N
I
SW10
E
T
U
N
I
M
O
T
U
A
SW12
K
O
O
C
O
T
U
A
SW11
SHORT CUTS
SW9
SY
A
E
&
K
C
I
U
Q
SW8
)
(.
V ?
N
O
C
SW7
R
E
T
N
E
SW3
R
E
W
O
P
O
R
C
I
M
SW5
S
S
E
R
P
X
E
T
S
O
R
F
E
D
SW2
CARRY OUT 4R CHECKS.
Service_R-890SLM.indd 19
4/25/09 10:55:24 AM
