LG SolarDOM MP-9486SC Service Manual page 27

(TROUBLE 3) Display shows all figures set, but oven does not start cooking while
desired program times are set and START button is touched.
CONDITION
1.Setting time does
not count down
when touching
START button.
2. Fan motor,
c-motor or
oven lamp,
turntable
motor do not
turn on.
(TROUBLE 4) Oven seems to be operation but little heat is produced in oven load.
CONDITION
Output is low.
NOTE: Simple test of power output-conducted by heating one liter water for one min. if available.
Minimum 8.5 o C temperature rise is normal condition.
CHECK
Check continuity
of secondary
switch (with
door closed).
Check the con-
nection between
connector and
P.C.B assembly.
Check fan motor
c-motor.
Check oven lamp
turntable motor.
CHECK
Check the
power source
voltage.
Disconnect the
wire leads from
relay 4 and check
on and off time
with multitester.
Measure the
output power.
RESULT
No continuity.
continuity.
No continuity.
Continuity.
Abnormal.
Abnormal.
Normal.
RESULT
Lower than 90% of
rating voltage.
Normal.
Abnormal.
Normal.
Abnormal.
5-17
CAUSE
Defective
secondary switch
and secondary
switch wire
connector.
Defective P.C.B
assembly.
Loose connection.
Defective fan
motor, c-motor.
Defective oven
lamp turntable
motor.
CAUSE
Decrease in power
source voltage
with load.
Defective P.C.B
assembly.
Defective
magnetron.
REMEDY
Replace
secondary switch
and secondary
switch wire
connector.
Replace P.C.B
assembly.
Connection then
tightly.
Replace fan
motor, c-motor.
Replace oven
lamp turntable
motor.
REMEDY
Suggest customer
contact local
electric power
utility co. or
qualified
electrician.
Replace P.C.B
assembly.
Replace
magnetron.