Kenmore 721.63662 Service Manual page 34

(TROUBLE 3) Display shows all figures set, but oven does not start cooking while desired
program times are set and START pad is touched.
CONDITION
1. Setting time
does not count
down when
touching START
pad.
2. Fan motor or
oven lamp do
not turn on.
Check the
3. The display
connection between
shows F-9.
magnetron, door &
control PCB and
inverter module.
Check the Relay 2 of
control PCB assembly.
CHECK
Check continuity
of secondary
switch (with
door closed).
Check the con-
nection between
CN1 connector
and control PCB
assembly.
Check fan motor.
Check oven lamp.
Check the
inverter module.
Check the
Magnetron.
Check the power
source voltage.
RESULT
No continuity.
Continuity.
Continuity
No continuity
Abnormal
Abnormal
Normal
No continuity.
Continuity.
Abnormal
Normal
Abnormal
Normal
Abnormal
Normal
Abnormal
7-23
CAUSE
Defective
secondary switch.
Defective control
PCB assembly.
Loose connection.
Defective fan motor.
Defective oven lamp.
Loose connection.
Defective Relay2.
Defective inverter
module.
Defective
Magnetron.
Unsafe AC input
voltage.
REMEDY
Replace
secondary switch.
Replace control
PCB assembly.
Connect them
tightly.
Replace fan motor.
Replace oven lamp.
Connect them
tightly.
Replace control
PCB assembly.
Replace inverter
module.
Replace
Magnetron.
Suggest customer
contact local electric
power utility co. or
qualified electrician.