Panasonic NN-SM221WZPE Service Manual ▷ View online
5-11
COMPONENTS
TEST PROCEDURE
RESULTS
FAN MOTOR
(Wire leads removed)
(Wire leads removed)
TURNTABLE
MOTOR
(Wire leads removed)
MOTOR
(Wire leads removed)
Measure the resistance.
(Ohm-meter scale: R x 100)
(Ohm-meter scale: R x 100)
Measure the resistance.
(Ohm-meter scale: R x 1000)
(Ohm-meter scale: R x 1000)
Normal:
Abnormal:
∞ or several Ω
Abnormal:
∞ or several
NOTE : • A MICROWAVE LEAKAGE TEST MUST ALWAYS BE PERFORMED WHEN THE UNIT IS
SERVICED FOR ANY REASON.
• MAKE SURE THE WIRE LEADS ARE IN THE CORRECT POSITION.
• WHEN REMOVING THE WIRE LEADS FROM THE PARTS, BE SURE TO GRASP THE
• WHEN REMOVING THE WIRE LEADS FROM THE PARTS, BE SURE TO GRASP THE
CONNECTOR, NOT THE WIRES.
00~500
1
Ω
Normal: Approx.100~200K
Ω
Ω
5-12
TROUBLE SHOOTING
WHEN YOU GET A COMPLAINT FROM YOUR CUSTOMER, EVALUATE THE COMPLAINT CAREFULLY. IF
THE FOLLOWING SYMPTOMS APPLY, PLEASE INSTRUCT THE CUSTOMER IN THE PROPER USE OF THE
MICROWAVE OVEN. THIS CAN ELIMINATE AN UNNECESSARY SERVICE CALL.
THE FOLLOWING SYMPTOMS APPLY, PLEASE INSTRUCT THE CUSTOMER IN THE PROPER USE OF THE
MICROWAVE OVEN. THIS CAN ELIMINATE AN UNNECESSARY SERVICE CALL.
CAUTIONS
1. Check grounding before checking for trouble.
2. Be careful of the high voltage circuit.
3. Discharge the high voltage capacitor. (See page 2-1)
4. When checking the continuity of the switches or of the high voltage transformer, disconnect one lead wire
2. Be careful of the high voltage circuit.
3. Discharge the high voltage capacitor. (See page 2-1)
4. When checking the continuity of the switches or of the high voltage transformer, disconnect one lead wire
from these parts and then check continuity with the AC plug removed. To do otherwise may result in a
false reading or damage to your meter.
false reading or damage to your meter.
5. Do not touch any part of the circuitry on the digital programmer circuit since static electric discharge may
damage this control panel.
Always touch yourself ground while working on this panel to discharge any static charge built up in your
body.
CONDITION
Microwave oven
does not work.
Inserting many plug into one
plug outlet and using
them at the same time
(causes overloading).
plug outlet and using
them at the same time
(causes overloading).
Microwave oven plug is not
inserted tightly.
inserted tightly.
Output power is too low.
Low AC input voltage.
Food temperature is too low.
Using metallic ware and
allowing it to touch the oven
wall.
allowing it to touch the oven
wall.
Sparks occurring.
Inconsistent intensity of
microwave by their
characteristics.
microwave by their
characteristics.
1. Wrap the thinner part with
aluminum foil.
2. Use plastic wrap or lid.
3. Stir once or twice while cooking
3. Stir once or twice while cooking
soup, cocoa or milk, etc.
Uneven cooking.
Ceramic ware trimmed in
gold or silver powder is used.
gold or silver powder is used.
Avoid using other electrical
appliances when you use the
microwave oven.
appliances when you use the
microwave oven.
Insert microwave oven plug
securely.
securely.
Use the microwave oven at
adequate line voltage.
adequate line voltage.
This may not be a defect.
It is possible that the food
should be cooked for a
longer time period.
It is possible that the food
should be cooked for a
longer time period.
Do not use metallic ware for
cooking except where noted
in the cooking guide.
cooking except where noted
in the cooking guide.
Do not use any type of
cookware with metallic
trimming.
cookware with metallic
trimming.
CAUSE
REMEDY
Excessive weight on tray or
improperly balanced.
improperly balanced.
Distribute food evenly. Cook
smaller portions and,or use
lighter weight cookware.
smaller portions and,or use
lighter weight cookware.
Turntable drags or makes
noise.
noise.
5-13
CONDITION
CHECK
RESULT
CAUSE
REMEDY
1. Fuse blows.
Continuity.
No continuity.
Continuity.
Shorted contact at
the primary switch.
Replace fuse,
primary, monitor,
and secondary
switches.
No continuity.
Normal.
Defective high
voltage capacitor.
Replace high
voltage capacitor.
Fuse blows again
Defective high volt-
age transformer.
age transformer.
Replace highvolt-
age transformer.
age transformer.
Malfunction of the
monitor switch.
Replace fuse,
primary, monitor,
and secondary
switches.
Check continuity
of monitor
switch (with
door closed).
Check continuity
of primary
switch (with
door opened).
Disconnect one
side of the wire
lead connected
from transformer
to the high
voltage
capacitor and
operate the unit.
Replace fuse
(TROUBLE 1) Oven lamp does not turn on when the timer knob is
with door closed.
This fuse is a special type of fuse which is kept as spare part by the importer.
NOTE :All these switches must be replaced at the same time.
rotated
5-14
CONDITION
CHECK
RESULT
CAUSE
REMEDY
Output is low
Lower than 198V.
Normal
Less than 6˚ C.
Faulty magnetron.
Replace.
Decrease in power
source voltage
with load.
Suggest customer
contact local
electric power
utility co.or
qualified
electrician.
Check the
power source
voltage
oscillating.
Measure the
magnetron ’s
output(See test
procedure).
(TROUBLE 3) Output power is low.
CONDITION
CHECK
RESULT
CAUSE
REMEDY
1.Oven does not
operate.
No continuity.
No continuity.
No continuity.
No continuity.
Malfunction of the
primary switch.
Malfunction of the
secondary switch.
Malfunction of the
timer switch.
timer switch.
Faulty thermostat.
Adjust or replace.
Adjust or replace.
replace.
replace.
Check the
continuity of the
primary switch
with door
closed.
continuity of the
primary switch
with door
closed.
Check the
continuity of the
secondary
switch with
secondary
switch pushed.
continuity of the
secondary
switch with
secondary
switch pushed.
Check the
continuity of the
timer switch
contacts.
continuity of the
timer switch
contacts.
Check the
continuity of the
thermostat.
continuity of the
thermostat.
(TROUBLE 2)Oven does not start even though the timer is set.
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