LG MC-783RC Service Manual ▷ View online
SCHEMATIC DIAGRAM
9
MICROWAVE
GRILL/CONV. OVEN
GRILL/CONV. OVEN
DIAGRAM SCHEMATIC
PRIMARY
SWITCH
BN
RD
RD
NO
MONITOR
SWITCH
COM
7 6 5 4 3 2 1
OVEN
THERMOSTAT
MAGNETRON
THERMOSTAT
BL
BL
N
L
O.L
F.M
T.T.M
YL
YL
WH
BN
WH
RD
10A
NOISE
FILTER
G - Y
INPUT
POWER
P O W E R
T R A N S
1
2
3
2
3
1 2 3
GN
GN
SECONDARY
SWITCH
PK
WH
WH
MAGNETRON
H.V DIODE
CAPACITOR
H.V
H.V
FUSE
0.8A
RD
RD
RD
F
FA
BL
BL
BL
NC
BN
BL
PK
PK
WH
SOLENOID
YL
BL
WH
RD
RD
RD
TRANSFORMER
RELAY 1
GRILL HEATER
YL
CONVECTION HEATER
RELAY 5
RELAY 2
230VAC
24VAC
COM.
YL
RELAY 4
RELAY 3
YL
WH
YL
RD
THERMISTOR
PCB
ACHTUNG
Hochspannungskondesator vor allen
Servicearbeiten gegen Masse entladen.!!
Servicearbeiten gegen Masse entladen.!!
AVANT INTERVENTION TECHNIQUE, DECONNECTER ET
DECHARGER LA CAPACITE DE HAUT VOLTAGE.
DECHARGER LA CAPACITE DE HAUT VOLTAGE.
B E F O R E S E R V I C N G D i s c h a r g e t h e h i g h v o i t a g e
C a p a c i t o r b y s h o r t i n g t h e n e g a t i v e h i g h v o l t a g e
T e r m i n a l o f i t t o c h a s s i s g r o u n d .
C a p a c i t o r b y s h o r t i n g t h e n e g a t i v e h i g h v o l t a g e
T e r m i n a l o f i t t o c h a s s i s g r o u n d .
*NOTE:DOOR IS CLOSE.
BN:BROWN BL:BLUE YL:YELLOW
RD:RED WH:WHITE PK:PINK
G-Y:GREEN AND YELLOWSTRIPED.
F.M:FAN MOTOR
O.L:OVEN LAMP
T.T.M: TURN TABLE MOTOR
C.M:CIRCULATION MOTOR
RD:RED WH:WHITE PK:PINK
G-Y:GREEN AND YELLOWSTRIPED.
F.M:FAN MOTOR
O.L:OVEN LAMP
T.T.M: TURN TABLE MOTOR
C.M:CIRCULATION MOTOR
C.M
RD
P/NO.3854W3A270A
PRIMARY
SWITCH
BN
RD
RD
NO
MONITOR
SWITCH
COM
7 6 5 4 3 2 1
OVEN
THERMOSTAT
MAGNETRON
THERMOSTAT
BL
BL
N
L
O.L
F.M
T.T.M
YL
YL
WH
BN
WH
RD
10A
NOISE
FILTER
G - Y
INPUT
POWER
P O W E R
T R A N S
1
2
3
2
3
1 2 3
GN
GN
SECONDARY
SWITCH
PK
WH
WH
MAGNETRON
H.V DIODE
CAPACITOR
H.V
H.V
FUSE
0.8A
RD
RD
RD
F
FA
BL
BL
BL
NC
BN
BL
PK
PK
WH
SOLENOID
YL
BL
WH
RD
RD
RD
TRANSFORMER
RELAY 1
GRILL HEATER
YL
CONVECTION HEATER
RELAY 5
RELAY 2
230VAC
24VAC
COM.
YL
RELAY 4
RELAY 3
YL
WH
YL
RD
THERMISTOR
PCB
ACHTUNG
Hochspannungskondesator vor allen
Servicearbeiten gegen Masse entladen.!!
Servicearbeiten gegen Masse entladen.!!
AVANT INTERVENTION TECHNIQUE, DECONNECTER ET
DECHARGER LA CAPACITE DE HAUT VOLTAGE.
DECHARGER LA CAPACITE DE HAUT VOLTAGE.
B E F O R E S E R V I C N G D i s c h a r g e t h e h i g h v o i t a g e
C a p a c i t o r b y s h o r t i n g t h e n e g a t i v e h i g h v o l t a g e
T e r m i n a l o f i t t o c h a s s i s g r o u n d .
C a p a c i t o r b y s h o r t i n g t h e n e g a t i v e h i g h v o l t a g e
T e r m i n a l o f i t t o c h a s s i s g r o u n d .
*NOTE:DOOR IS CLOSE.
BN:BROWN BL:BLUE YL:YELLOW
RD:RED WH:WHITE PK:PINK
G-Y:GREEN AND YELLOWSTRIPED.
F.M:FAN MOTOR
O.L:OVEN LAMP
T.T.M: TURN TABLE MOTOR
C.M:CIRCULATION MOTOR
RD:RED WH:WHITE PK:PINK
G-Y:GREEN AND YELLOWSTRIPED.
F.M:FAN MOTOR
O.L:OVEN LAMP
T.T.M: TURN TABLE MOTOR
C.M:CIRCULATION MOTOR
C.M
RD
P/NO.3854W3A269A
R.M
RD
YL
R.M:ROTISSERIE MOTOR
H.V
H.V
MODEL:MC-783MC
MODEL:MC-783RC
MICROWAVE/GRILL/
CONVECTION OVEN
CONVECTION OVEN
SERVICE MANUAL
MODEL : MC-783MC / MC-783RC
CAUTION
BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS
IN THIS MANUAL.
IN THIS MANUAL.
19
COMPONENTS TEST
PROCEDURE RESULTS
HIGH VOLTAGE
CAPACITOR
CAPACITOR
Antenna
Gasket
Filament
Terminals
Terminals
Chassis
Normal : Momentary indicates
several ohms, and
then gradually
returns to infinite.
then gradually
returns to infinite.
Normal :
°
.
NOTE : When testing the magnetron, be sure to install the magnetron gasket in
the correct position and be sure that the gasket is in good condition.
Measure the resistance.
(Multi-meter scale : Rx1000)
(Multi-meter scale : Rx1000)
●
Terminal to termonal.
Measure the resistance.
(Multi-meter scale : Rx1000)
(Multi-meter scale : Rx1000)
●
Terminal to case.
Measure the continuity (Forward).
(Multi-meter scale : Rx10000)
(Multi-meter scale : Rx10000)
Measure the continuity (Reverse).
(Multi-meter scale : Rx10000)
(Multi-meter scale : Rx10000)
Normal :
°
.
Abnormal : Continuity.
Normal : Continuity.
Abnormal :
Abnormal :
°
.
HIGH VOLTAGE
DIODE
DIODE
NOTE :
Some inexpensive
meter may indicate
infinite resistance in
both direction.
Some inexpensive
meter may indicate
infinite resistance in
both direction.
20
COMPONENTS TEST
PROCEDURE
RESULTS
HEATER ELEMENT
(Wire leads removed)
(Wire leads removed)
FUSE, H.V. FUSE
(Wire leads removed.)
(Wire leads removed.)
Normal
Abnormal
0¡c~Approx 150¡C
Approx 150¡C
OVEN THERMOSTAT
MAGNETRON
THERMOSTAT
MAGNETRON
THERMOSTAT
Normal :
●
Grill heater
Approx. 40.7 ½
(at 20~30¡C)
Approx. 40.7 ½
(at 20~30¡C)
Normal : more than 0.5M ½
Measure the resistance with 500V-100M
½ insulation resistance meter.
½ insulation resistance meter.
Measure the resistance.
(Multi-meter scale : Rx1)
(Multi-meter scale : Rx1)
Check for continuity of the switch with a
Multi-meter.
Multi-meter.
NOTE : If the fuse is blown, check the primary, the secondary, and the monitor
switches, H.V.D. and H.V.C. before replacing the fuse.
If the fuse is blown by improper switch operation replace the defective
switch and the fuse at the same time.
Replace just the fuse if the switches operate normally.
If the fuse is blown by improper switch operation replace the defective
switch and the fuse at the same time.
Replace just the fuse if the switches operate normally.
NOTE : Make sure heater is fully cooled when tested.
Click on the first or last page to see other MC-783RC service manuals if exist.