SAMSUNG M959AMF Service Manual

MICROWAVE OVEN

M959 (WHITE) / M959C (RED)
M959GR (GREEN)

SERVICE

Manual

MICROWAVE OVEN CONTENTS

1 min +

1. 2. 3.

Auto

Auto

Auto

1. 2. 3.

1. 2. 3.

1. Precaution

2. Specifications

3. Operating Instructions

4. Disassembly and Reassembly

5. Alignment and Adjustments

6. Troubleshooting

7. Exploded Views and Parts List

8. PCB Diagrams

9. Schematic Diagrams

Samsung Electronics

(a) Do not operate or allow the oven to be

operated with the door open.

(b) Make the following safety checks on

all ovens to be serviced before activating
the magnetron or other microwave
source, and make repairs as necessary:
(1) Interlock operation,
(2) proper door closing,
(3) seal and sealing surfaces (arcing,

wear, and other damage),

(4) damage to or loosening of hinges

and latches,

(5) evidence of dropping or abuse.

(c) Before turning on microwave power

for any service test or inspection within
the microwave generating
compartments, check the magnetron,
wave guide or transmission line, and
cavity for proper alignment, integrity,
and connections.

(d) Any defective or misadjusted

components in the interlock, monitor,
door seal, and microwave generation
and transmission systems shall be
repaired, replaced, or adjusted by
procedures described in this manual
before the oven is released to the owner.

(e) A Microwave leakage check to verify

compliance with the Federal
performance standard should be
performed on each oven prior to release
to the owner.

PRECAUTIONS TO BE OBSERVED BEFORE AND DURING
SERVICING TO A VOID POSSIBLE EXPOSURE TO EXCESSIVE
MICROWAVE ENERGY

1. Precaution

1-1 Safety precautions ( )

Samsung Electronics 1-1

1. All repairs should be done in accordance
with the procedures described in this
manual. This product complies with
Federal Performance Standard 21 CFR
Subchapter J (DHHS).

2. Microwave emission check should be
performed to prior to servicing if the oven is
operative.

3. If the oven operates with the door open :
Instruct the user not to operate the oven and
contact the manufacturer and the center for
devices and radiological health immediatly.

4. Notify the Central Service Center if the
microwave leakage exceeds 5 mW/cm

2

5. Check all grounds.

6. Do not power the MWO from a "2-prong"
AC cord. Be sure that all of the built-in
protective devices are replaced. Restore any
missing protective shields.

7. When reinstalling the chassis and its
assemblies, be sure to restore all protective
devices, including: nonmetallic control
knobs and compartment covers.

8. Make sure that there are no cabinet openings
through which people--particularly
children--might insert objects and contact
dangerous voltages. Examples: Lamp hole,
ventilation slots.

9. Inform the manufacturer of any oven found
to have emmission in excess of 5 mW/cm2,
Make repairs to bring the unit into
compliance at no cost to owner and try to
determine cause.
Instruct owner not to use oven until it has
been brought into compliance.

CENTRAL SERVICE CENTER

10. Service technicians should remove their
watches while repairing an MWO.

11. To avoid any possible radiation hazard,
replace parts in accordance with the wiring
diagram. Also, use only the exact
replacements for the following parts:
Primary and secondary interlock switches,
interlock monitor switch.

12. If the fuse is blown by the Interlock Monitor
Switch: Replace all of the following at the
same time: Primary and secondary switches,
as well as the Interlock Monitor Switch. The
correct adjustment of these switches is
described elsewhere in this manual. Make
sure that the fuse has the correct rating for
the particular model being repaired.

13. Design Alteration Warning:
Use exact replacement parts only, i.e.,
only those that are specified in the
drawings and parts lists of this manual.
This is especially important for the
Interlock switches, described above.
Never alter or add to the mechanical or
electrical design of the MWO. Any design
changes or additions will void the
manufacturer's warranty.10.Always unplug
the unit's AC power cord from the AC
power source before attempting to
remove or reinstall any component or
assembly.

14. Never defeat any of the B+ voltage
interlocks. Do not apply AC power to the
unit (or any of its assemblies) unless all
solid-state heat sinks are correctly installed.

15. Some semiconductor ("solid state") devices
are easily damaged by static electricity. Such
components are called Electrostatically
Sensitive Devices (ESDs). Examples include
integrated circuits and field-effect
transistors.

Immediately before handling any
semiconductor components or assemblies,
drain the electrostatic charge from your
body by touching a known earth ground.

16. Always connect a test instrument's ground
lead to the instrument chassis ground before
connecting the positive lead; always remove
the instrument's ground lead last.

Follow these special safety precautions. Although the microwave oven is completely safe during ordinary
use, repair work can be extremely hazardous due to possible exposure to microwave radiation, as well as
potentially lethal high voltages and currents.

17. When checking the continuity of the witches
or transformer, always make sure that the
power is OFF, and one of the lead wires is
disconnected.

18. Components that are critical for safety are
indicated in the circuit diagram by
shading, or .

19. Use replacement components that have the
same ratings, especially for flame resistance
and dielectric strength specifications. A
replacement part that does not have the
same safety characteristics as the original
might create shock, fire or other hazards.

1. High Voltage Warning
Do not attempt to measureany of the high
voltages--this includes the filament voltage
of the magnetron. High voltage is present
during any cook cycle.

Before touching any components or wiring,
always unplug the oven and discharge the
high voltage capacitor (See Figure 1-1)

2. The high-voltage capacitor remains charged
about 30 seconds after disconnection. Short
the negative terminal of the high-voltage
capacitor to to the oven chassis. (Use a
screwdriver.)

3. High voltage is maintained within specified
limits by close-tolerance, safety-related
components and adjustments. If the high
voltage exceeds the specified limits, check
each of the special components.

1-2

Pretaution

Samsung Electronics

1-2 Special Servicing Precautions (Continued)

1-3 Special High Voltage Precautions

Fig. 1-1. Discharging the High Voltage Capacitor

2. Specifications

2-1 Table of Specifications

Samsung Electronics 2-1

TIMER 99 MINUTES 90 SECONDS
POWER SOURCE 230V 50Hz, AC
POWER CONSUMPTION MICROWAVE : 1,550W
OUTPUT POWER FROM 100 TO 1000W (10 LEVEL POWER)

(IEC-705 TEST PROCEDURE)
OPERATING FREQUENCY 2,450MHz
MAGNETRON OM75PH(31)
COOLING METHOD COOLING FAN MOTOR
OUTSIDE DIMENSIONS 517(W) x 297(H) x 395(D)

POWER LEVEL

% M959

10% 90W 4 sec 26 sec
20% 180W 7 sec 23 sec
30% 270W 10 sec 20 sec
40% 360W 13 sec 17 sec
50% 450W 16 sec 14 sec
60% 540W 19 sec 11 sec
70% 630W 22 sec 8 sec
80% 720W 25 sec 5 sec
90% 810W 28 sec 2 sec

100% 900W 30 sec 0 sec

ON TIME OFF TIME

2-2 Comparison Chart

MODEL

FEATURE

AUTO REHEAT O
AUTO COOK O
POWER LEVEL O
TIME SETTING AND WEIGHT O
AUTO DEFROST O
DEODORIZATION O

M959/ M959C / M959GR

Auto Reheat Programs
Auto Cook Programs
Power Level Button

Auto Defrost Programs
Time Setting

and Weight Selection

Cancel Button

Deodorization Button
Start Button

Auto

M959

/g

/Kg

/10s.

1min

10min

1 min +

Auto

Auto

1. 2. 3.

1. 2. 3.

1. 2. 3.

3. Operating Instructions

3-1 Control Panel

Samsung Electronics 3-1

3-2 Features & External Views

Door

Ventilation Holes

Light

Safety Interlock Holes

Control Panel

Display

Roller Ring

Coupler

Glass Plate

Door Latches

Auto

M959

/g

/Kg

/ 10s.

1min

10min

1 min +

1. 2. 3.

Auto

Auto

1. 2. 3.

1. 2. 3.

517mm

297mm

395mm

/

g

/kg

/10s.

1min

10min

1 min +

1. 2. 3.

Auto

Auto

Auto

1. 2. 3.

1. 2. 3.

4. Disassembly and Reassembly

4-1 Replacement of Magnetron, Motor Assembly and Lamp

Samsung Electronics 4-1

Remove the magnetron including the shield case,
permanent magnet, choke coils and capacitors (all
of which are contained in one assembly).

1. Disconnect all lead wires from the magnetron
and lamp.

2. Remove a screw securing the magnetron
supporter.

3. Remove the magnetron supporter.

4. Remove the air cover.

5. Remove screws securing the magnetron to the
wave guide.

6. Take out the magnetron very carefully.

7. Remove screws from the back panel.

8. Take out the fan motor.

9. Remove the oven lamp by rotating to pull out
from hole of air cover.

NOTE1: When removing the magnetron, make

sure that its antenna does not hit any
adjacent parts, or it may be damaged.

NOTE2: When replacing the magnetron, be sure

to remount the magnetron gasket in
the correct position and make sure the
gasket is in good condition.

1. Discharge the high voltage capacitor.

2. Disconnect all the leads.

3. Remove the mounting bolts.

4. Reconnect the leads correctly and firmly.

4-1 Replacement of High Voltage Transformer

Lamp

Magnetron

H. V. Trans

H. V. Capacitor

Screw

Thermo S/WCover Air

Fan Motor

H. V. Trans

Screws

PRECAUTION

Servicemen should remov their watches whenever

working close to or replacing the magnetron.

PRECAUTION

There exists HIGH VOLTAGE ELECTRICITY with high

current capabilities in the circuits of the HIGH
VOLTAGE TRANSFORMER secondary and filament
terminals. It is extremely dangerous to work on or
near these circuits with the oven energized.
DO NOT measure the voltage in the high voltage
circuit including filament voltage of magnetron.

4-3 Replacement of Door Assembly

4-3-1 Removal of Door Assembly

4-2 Samsung Electronics

Remove hex bolts securing the upper hinge and
lower hinge. Then remove the door assembly.

Insert flat screwdriver into the gap between Door
"E" and Door "C" to remove Door "C". Be careful
when handling Door "C" because it is fragile.

Following the procedure as shown in the figure,
insert and bend a thin metal plate between Door
"E" and Door "A" until you hear the 'tick' sound.

1. Insertion depth of the thin metal plate should be

0.5mm or less.

Remove pin hinge from Door "E"

Detach spring from Door "E" and key door.

4-3-2 Removal of Door "C"

4-3-3 Removal of Door "E"

4-3-4 Removal of Key Door & Spring

Disassembly and Reassembly

Upper Hinge

Lower Hinge

Screws

Screws

Key Door Spring

Door "E"

4-3-5 Reassembly Test

Samsung Electronics 4-3

1. Disconnect the oven from the power source.

2. Remove the 10A fuse in the fuse holder.

3. When replacing the 10A fuse, be sure to use an

exact replacement part. If new 10A fuse blows
out again after replacement, check the primary
interlock switch, door sensing switch and
interlock monitor switch.

4. When the above three switches operate properly,

check if any other part such as the control circuit
board, blower motor or high voltage
transformer is defective.

1. Take out the glass tray, guide roller and coupler

from cavity.

2.

Turn the oven upside down to replace the drive motor.

3. Remove a screw securing the drive motor cover.

4. Disconnect all the lead wires from the drive motor.

5. Remove screws securing the drive motor to the

cavity.

6. Remove the drive motor.

7. When replacing the drive motor, be sure to

remount it in the correct position.

8. Connect all the leads to the drive motor.

9. Screw the deive motor cover to the base plate

with a screw driver.

10. Remount the coupler in the correct position.

4-4 Replacement of Fuse

4-5 Replacement of Drive Motor

Disassembly and Reassembly

Screw

Drive Motor Cover

Base Plate

Drive Motor

After replacement of the defective component parts of the door, reassemble it and follow the instructions below for proper

installation and adjustment so as to prevent an excessive microwave leakage.

1. When mounting the door to the oven, be sure to adjust the door parallel to the bottom line of the oven
face plate by moving the upper hinge and lower hinge in the direction necessary for proper alignment.

2. Adjust so that the door has no play between the inner door surface and oven front surface. If the door
assembly is not mounted properly, microwave energy may leak from the space between the door and
oven.

3. Do the microwave leakage test.

4-6 Replacement of Control Circuit Board

4-6-1 Removal of Ass'y Control Box

4-4 Samsung Electronics

1. Be sure to ground any static electric charge in
your body and never touch the touch control
circuitry.

2. Disconnect the connectors from the control
circuit board.

3. Remove screws securing the control box
assembly.

4. Remove the screw securing the ground tail of
the keyboard.

1. Pull the lever end of the plastic fastener and
remove the Flexible Printed Circuit(FPC) of
membrane panel.

2. Remove screws securing the control circuit
board.

3. Lift up the control circuit board from the Ass'y
control box.

4. When reconnecting the FPC connector, make
sure that the holes on the connector are properly
engaged with the hooks on the Plastic Fastener.

CONTROL BOX

SCREW

4-6-2 Remonal of Ass'y P.C.B

FPC
Connector

screw

screw

Disassembly and Reassembly

Samsung Electronics

5. Alignment and Adjustments

5-1 High Voltage Transformer

5-2 Low Voltage Transformer

5-3 Magnetron

5-1

1. Remove connectors from the transformer terminals
and check continuity.

2. Normal resistance readings are as follows:

(Room temperature = 20ûC)

1. Continuity checks can indicate only an open
filament or a shorted magnetron. To diagnose an
open filament or shorted magnetron :

2. Isolate the magnetron from the circuit by
disconnecting its leads.

3. A continuity check across the magnetron filament
terminals should indicate one ohm or less.

4. A continuity check between each filament terminal
and magnetron case should read open.

1. The low voltage transformer is located on the
control circuit board.

2. Remove the low voltage transformer from the
PCB Ass'y and check continuity.

3. Normal resistor reading is shown in the table.

Filament Terminals

Secondary

Terminal

Primary
Terminals

MODEL

M959/ M959C / M959GR

Secondary Approx. 130W

Filament Approx.0W
Primary Approx.1.700W

Terminals Resistance
1~2(Input) 1,000W

3~4(Output 2.9V) 3.947W

5~6(Output13V) 2.117W

Cooling Fins

Gasket Plate

Magnetron Antenna

PRECAUTION

1. High voltage is present at the high voltage terminals during any cook cycle.

2. It is neither necessary nor advisable to attempt measurement of the high voltage.

3. Before touching any oven components or wiring, always unplug the oven from its power source and discharge the high
voltage capacitor.

1. When mounting Primary switch and Interlock
Monitor switch to Latch Body, consult the figure.

2. No specific adjustment during installation of
Primary switch and Monitor switch to the latch
body is necessary.

3. When mounting the Latch Body to the oven
assembly, adjust the Latch Body by moving it so
that the oven door will not have any play in it.
Check for play in the door by pulling the door
assembly. Make sure that the latch keys move
smoothly after adjustment is completed.
Completely tighten the screws holding the Latch
Body to the oven assembly.

4. Reconnect to Monitor switch and check the
continuity of the monitor circuit and all latch
switches again by following the components test
procedures.

5. Confirm that the gap between the switch
housing and the switch actuator is no more than

0.5mm when door is closed.

Samsung Electronics

5-4 High Voltage Capacitor

5-5 High Voltage Diode

5-6 Main Relay and Power Control Relay

5-7 Adjustment of Primary Switch, Door Sensing Switch and Monitor Switch

5-2

1. Check continuity of the capacitor with the meter set at the highest resistance scale.

2. Once the capacitor is charged, a normal capacitor shows continuity for a short time, and then indicates 9MW.

3. A shorted capacitor will show continuous continuity.

4. An open capacitor will show constant 9MW.

5. Resistance between each terminal and chassis should read infinite.

1. Isolate the diode from the circuit by disconnecting its leads.

2. With the ohm-meter set at the highest resistance scale, measure across the diode terminals. Reverse the
meter leads and read the resistance. A meter with 6V, 9V or higher voltage batteries should be used to
check the front-to back resistance of the diode (otherwise an infinite resistance may be read in both
directions). The resistance of a normal diode will be infinite in one direction and several hundred KW in
the other direction.

1. The relays are located on the PCB Ass'y. Isolate them from the main circuit by disconnecting the leads.

2. Operate the microwave oven with a water load in the oven. Set the power level set to high.

3. Check continuity between terminals of the relays after the start pad is pressed.

Precaution

For continued protection against radiation hazard, replace parts in accordance with the wiring diagram and be sure to use the
correct part number for the following switches: Primary and secondary interlock switches, and the interlock monitor switch
(replace all together). Then follow the adjustment procedures below. After repair and adjustment, be sure to check the continuity
of all interlock switches and the interlock monitor switch.

Alignment and Adjustments

Door Open Door Closed
Primary switch ¥ 0
Monitor switch (COM-NC) 0 ¥
Monitor switch (COM-NO) ¥ 0
Door Sensing S/W ¥ 0

Primary Interlock Switch

Lever Door(B)

Body Latch

Door Sensing
Switch

Interlock
Monitor
Switch

5-2

Samsung Electronics 5-3

The output power of the magnetron can be measured by performing a water temperature rise test.
Equipment needed :
* Two 1-liter cylindrical borosilicate glass vessel (Outside diameter 190 mm)
* One glass thermometer with mercury column
NOTE: Check line voltage under load. Low voltage will lower the magnetron output. Make all temperature
and time tests with accurate equipment.

1. Fill the one liter glass vessel with water.

2. Stir water in glass vessel with thermometer, and record glass vessel's temperature ("T1", 10±1ûC).

3. After moving the water into another glass vessel, place it in the center of the cooking tray. Set the oven to high
power and operate for 54 seconds exactly. (2 seconds included as a holding time of magnetron oscillation:)

4. When heating is finished, stir the water again with the thermometer and measure the temperature ("T2").

5. Subtract T1 from T2. This will give you the water temperature rise. (DT)

6. The output power is obtained by the following formula;

* Output (W) = 100 x DT

7. Normal temperature rise for this model is 9ûC to 11ûC at 'HIGH'.
NOTE 1: Variations or errors in the test procedure will cause a variance in the temperature rise.
Additional power test should be made if temperature rise is marginal.
NOTE 2: Output power in watts is computed by multiplying the temperature rise (step E) by a factor of 91
times the of centigrade temperature.

The microwave heat distribution can be checked indirectly by measuring the water temperature rise at
certain positions in the oven:

1. Prepare five beakers made of 'Pyrex', having 100 milliliters capacity each.

2. Measure exactly 100milliliters off water load with a measuring cylinder, and pour into each beaker.

3. Measure the temperature of each water load. (Readings shall be taken to the first place of decimals.)

4. Put each beaker in place on the cooking tray as illustrated in figure below. Start heating.

5. After heating for 2 minutes, measure the water temperature in each beaker.

6. Microwave heat distribution rate can be calculated as follows:

Minimum

Temperature Rise

Heat Distribution = X 100(%)

Maximum

Temperature Rise

The result should exceed 65%.

4.187 x 1000 x DT

Output Power =

42

42 : Heating Time (sec)

4.187 : Coefficient for Water
1000 : Water (cc)
DT : Temperature Rise (T2-T1)

5-8 Output Power of Magnetron

5-9 Microwave Heat Distribution - Heat Evenness

Alignment and Adjustments

D

D

D/4

D/4

D/4

D/4

Cooking Tray

Beaker

CAUTION

MICROWAVE RADIATION

PERSONNEL SHOULD NOT ALLOW EXPOSURE TO MICROWAVE RADIATION FROM MICROWAVE GENERATOR OR OTHER PARTS
CONDUCTING MICROWAVE ENERGY.

Samsung Electronics

1) Pour 275¡ 15cc of 20¡ 5¡ ( 68¡ 9¢ ) water in a

beaker which is graduated to 600cc, and place the
beaker in the center of the oven.

2) Start to operate the oven and measure the leakage by
using a microwave energy survey meter.

3) Set survey meter with dual ranges to 2,450MHz.

4) When measuring the leakage, always use the 2 inch
spacer cone with the probe. Hold the probe
perpendicular to the cabinet door. Place the spacer
cone of the probe on the door and/or cabinet door
seam and move along the seam, the door viewing
window and the exhaust openings moving the
probe in a clockwise direction at a rate of 1 inch/sec. If the leakage testing of the cabinet door seam is
taken near a corner of the door, keep the probe perpendicular to the areas making sure that the probe end
at the base of the cone does not get closer than 2 inches to any metal. If it gets closer than 2 inches,
erroneous readings may result.

5) Measured leakage must be less than 4mW/cm2, after repair or adjustment.

Alignment and Adjustments

1 min +

1. 2. 3.

Auto

Auto

Auto

1. 2. 3.

1. 2. 3.

5-13 Leakage Measuring Procedure

5-10 Procedure for Measurement of Microwave Energy Leakage

5-12Note on Measurement

5-11 Check for Microwave Leakage

5-13-1 Record keeping and notification after measurement

1) After adjustment and repair of a radiarion preventing device, make a repair record for the measured
values, and keep the data.

2) If the radiation leakage is more than 4 mW/§† after determining that all parts are in good condition,
functioning properly and the identical parts are replaced as listed in this manual notift that fact to ;

CENTRAL SERVICE CENTER

5-13-2 At least once a year have the microwave energy survey meter checked for accuracy by its

manufacturer.

1. Remove the outer panel.

2. Pour 275±15cc of 20±5ûC(68±9ûF) water in a beaker
which is graduated to 600cc, and place the beaker in
the center of the oven.

3. Start the oven at the highest power level.

4. Set survey meter dual ranges to 2,450MHz.

5. Using the survey meter and spacer cone as described

above, measure arnear the opening of magnetron, the
surface of the air guide and the surface of the wave
guide as shown in the following photo.( but avoid the
high voltage components.) The neading should be less
than 4mW/cm2.

1) Do not exceed the limited scale.

2) The test probe must be held on the grip of the handle, otherwise a false reading may result when the
operator's hand is between the handle and the probe.

3) When high leakage is suspected, do not move the probe horizontally along the oven surface; this may
cause damage to the probe.

4) Follow the recommendation of the manufacturer of the microwave energy survey meter.

Maximum allowable leakage is 5mW/cm2.
4mW/cm2is used to allow for measurement and meter accuracy

5-4

Samsung Electronics

6. Troubleshooting

6-1

PRECAUTION

1. CHECK GROUNDING BEFORE CHECKING FOR TROUBLE.

2. BE CAREFUL OF THE HIGH VOLTAGE CIRCUIT.

3. DISCHARGE THE HIGH VOLTAGE CAPACITOR.

4. WHEN CHECKING THE CONTINUITY OF THE SWITCHES OR TRANSFORMER, DISCONNECT ONE LEAD WIRE FROM THESE
PARTS AND THEN CHECK CONTINUITY WITHOUT THE POWER SOURCE ON. TO DO OTHERWISE MAY RESULT IN A FALSE
READING OR DAMAGE TO YOUR METER.

5. DO NOT TOUCH ANY PART OF THE CIRCUIT OR THE CONTROL CIRCUIT BOARD, SINCE STATIC DISCHARGE MAY DAMAGE IT.
ALWAYS TOUCH GROUND WHILE WORKING ON IT TO DISCHARGE ANY STATIC CHARGE BUILT UP.

6-1 Electrical Maltunction

SYMPTOM CAUSE CORRECTIONS

Oven is dead. 1. Open or loose lead wire harness Check fan motor when thermal cutout is defective.
Fuse is OK. 2. Open thermal cutout (Magnetron)
No display and no operation at all. 3. Open low voltage transformer Check Ass'y PCB when LVT is defective.

4. Defective Ass'y PCB

No display and no operation at all. 1. Shorted lead wire harness Check adjustment of primary, interlock monitor,
Fuse is blown. 2. Defective primary latch switch (NOTE 1) door sensing switch.

3. Defective monitor switch (NOTE1)

4. Shorted HVCapacitor

5. Shorted HVTransformer (NOTE2)
NOTE 1: All of these switches must be replaced at the same time.

(refer to adjustment instructions)
Check continuity of power relay contacts and if it has continuity, replace power
relay also.

NOTE 2: When HVTransformer is replaced, check diode and magnetron also.

Oven does not accept 1. Key input is not in-Sequence Refer to operation procedure.
key input (Program) 2. Open or loose connection of membrane

key pad to Ass'y PCB

3. Shorted or open membrane panel

4. Defective Ass'y PCB Replace PCB main.

1. Off-alignment of latch switches Adjust door and latch switches.

2. Open or loose connection of high voltage
circuit especially magnetron filament
circuit

NOTE: Large contact resistance will bring

lower magnetron filament voltage and
Timer starts countdown but no cause magnetron to lower output and/or
microwave oscillation. intermittent oscillation.
(No heat while oven lamp and 3. Defective high voltage components Check high voltage component according to

fan motor turn on.) H.V.Transformer component test procedure and replace if it is

H.V.Capacitor defective.
H.V.Diode, H.V.Fuse
Magnetron

4. Open or loose wiring of power relay

5. Defective primary latch switch

6. Defective power relay or Ass'y PCB Replace PCB main.

Samsung Electronics6-2

Troubleshooting

SYMPTOM CAUSE CORRECTIONS

Oven lamp and fan motor turn on 1. Misadjustment or loose wiring Adjust door and latch switches.

of primary latch switch

2. Defective primary latch switch

Oven can program but timer 1. Open or loose wiring of secondary Adjust door and interlock switches.
does not start. interlock switch

2. Off-alignment of primary interlock

3. Defective secondary interlock S/W

Microwave output is low;. 1. Decrease in power source voltage. Consult electrician.
Oven takes longer time to 2. Open or loose wiring of magnetron
cook food. filament circuit. (Intermittent oscillation))

3. Aging of magnetron
Fan motor turns on when plugged in Loose wiring of door sensing switch Check wire of door sensing switch.
Oven does not operate and return Defective Ass'y PCB Replace PCB main.

to the plugged in mode.
Loud buzzing noise can be heard. 1. Loose fan and fan motor Tighten screws of fan motor.

2. Loose screws on H.V.Transformer Tighten screws of H.V.Transformer.

3. Shorted H.V.Diode Replace H.V.Diode.
Turntable motor does not rotate. 1. Open or loose wiring of turntable motor. Replace turntable motor.

2. Defective turntable motor.
Oven stops operation during cooking 1. Open or loose wiring of primary Adjust door and latch switches.

interlock switch

2. Operation of thermal cutout(Magnetron)
Sparks 1. Metallic ware or cooking dishes Inform the customer.

touching on the oven wall.

2. Ceramic ware trimmed with gold or Do not use any type of cookware with

silver powder also causes sparks. metallic trimming.

Uneven cooking Uneven intensity of microwave due to Wrap thinner parts of the food with

its characteristics. aluminum foil.

Use plastic wrap or cover with a lid.
Stir once or twice while cooking
foods such as soup, cocoa, or milk.

Noise from the turntable motor Noise may result from the motor. Replace turntable motor.
when it starts to operate.

6-1 Electrical Maltunction(continved)

Samsung Electronics

7. Exploded Views and Parts List

7-1 Exploded Views

7-1

M1

M2

M21

M22

M23

M24

M25

M26

M15

M14

M16

M18

M19

M20

M3

M30

M4

M5

M6

M7

M8

M30

M9

M10

M12

M13

M11

M29

M27

M28

M17

D1

D12

D2

D3

D4

D5

D6

D7

D9

D8

D10

D11

C2

C1

C3

C7

C5

C15

C8

C6

C10

C9

C11

C4

B1

B2

B2

B3

B4

NC

NO

COM

C12

C13

C14

7-2 Main Parts List

7-2 Samsung Electronics

Exploded Views and Parts List

Ref. No. Parts No. Description/Specification Q'ty Remarks

M 1 DE70-30001A PANEL-OUTER;SECC T0.6 360 1128 EPOXY-COATIN 1 WHITE
M 1 DE70-30001E PANEL-OUTER;SECC T0.6 360 1128 W/RED RE-44 1 RED
M 1 DE70-30001I PANEL-OUTER;SECC T0.6 360 1128 DEEP/GRN MX 1 GREEN
M 2 DE63-90035G CUSHION-RUBBER;DFA20 T2 W190 L100 BLK 1
M 3 DE39-20054C ASSY POWER CORD;KKP-4819D/B206 250V10A L150 1
M 4 DE39-40537A WIRE HARNESS-A;230V50HZ M945(SAW) 1
M 5 DE91-40093A ASSY NOISE FILTER;SN-E10D 250V 10A 1
M 6 DE31-10156A MOTOR-FAN;SMF-945EA 230/50 2400 M97G45 1
M 7 DE47-20009A THERMOSTAT;CS-7SA (160/60) 187Y 250V7.5A 160 1
M 8 DE03-30035A MAGNETRON;OM75PH(31)ESS 1
M 9 DE93-20020A ASSY BODY LATCH;RE-43B/90B 1
M 10 4713-001004 LAMP-INCANDESCENT;230V,-,40W,ORG,-,-,25x 1
M 11 DE61-50490A BRACKET-TCO;SECC1 T0.6 34 58 1
M 12 DE71-60016A COVER-AIR;PP 2 WHT M945/MB45 1
M 13 DE91-70101C ASSY-THERMOSTAT;MW5574W 160/60 187-HORIZ 1
M 14 DE73-90027A FERRITE CORE;NI-ZN T13.8 W21.0 L28.0 BNF 14 1
M 15 DE26-10100A TRANS-H.V;SHV-945EG1 230V 50HZ 2310V DPC 1
M 16 DE61-50106A BRACKET-HVC;SECC T0.8 W31 L125.8 1
M 17 2501-001019 C-OIL;1.01uF,2100V,BK,35x54x90,20mm 1
M 18 DE59-40001A DIODE-H.V;HVR-1X-32B-12 1
M 19 DE91-70061A ASSY-H.V.FUSE;THV060T-0800-H 5KV/0.8A WHT 1
M 20 DE61-40017A FOOT;PP(A353) BLK MW5630T 2
M 21 DE31-10154A MOTOR-DRIVE;M2HJ49ZR02,ST-16 1V 5/6 1
M 22 DE80-10001A BASE-PLATE;SGCC T0.8 345 565 1
M 23 DE47-20008A THERMOSTAT;PW2N-52JC 100/60 250V/7.5A H 1
M 24 DE71-60382A COVER-CEILING;MICASHEET T0.5 70 133 1
M 25 ASSY DOOR;M959/AMF WHT BASIC 1 WHITE
M 25 ASSY DOOR;M959C/AMF RED 1 RED
M 25 ASSY DOOR;M959GR/XEF GREEN 1 GREEN
M 26 ASSY CONTROL-BOX;230V50HZ M959 WHT 1 WHITE
M 26 ASSY CONTROL-BOX;230V50HZ M959CAMF RED 1 RED
M 26 ASSY CONTROL-BOX;230V50HZ M959GR/XEF GRN 1 GREEN
M 27 DE74-20015B TRAY-COOKING;GLASS T6.0 PI318 1050G MW5630T 1
M 28 DE92-90189D ASSY-GUIDE ROLLER;D19 STD 1
M 29 DE67-60075A COUPLER;PPS 7G BRN M97G45 1
M 30 DE63-90065N CUSHION-GUIDE;PUT-FOAM T10 W10 L200 BLK MW55 1
M 31 DE63-90065O CUSHION-GUIDE;PUT-FOAM T35 W20 L135 VBLK MW55 1

: Option Parts

: Warning

:Electrostatically Sensitive Devices

Samsung Electronics 7-3

Ref. No. Parts No. Description / Specification Q'ty Remarks

D 1 DE64-20112D HANDLE-DOOR;ABS(HR0370U) 30G WHT M959 1 WHITE
D 1 DE64-20112C HANDLE-DOOR;ABS BLK 30G RE-447 1 RED
D 1 DE64-20112E HANDLE-DOOR;ABS(HR0370D) 30G GRN M959GR 1 GREEN
D 2 DE01-00098A FILM-DOOR;PET T0.13 W22.6 L201.8 1 WHITE ONLY
D 3 DE64-40263F DOOR-A;ABS(HR-0370U) 160G WHT M959 1 WHITE
D 3 DE64-40263G DOOR-A;ABS(HR-0370U) 160G GRN M959GR NE 1 RED
D 3 DE64-40263H DOOR-A;ABS(HR-0370D) 160G GRN M959GR NE 1 GREEN
D 4 DE67-20265D DOOR-SCREEN;ACRYL (IF850)ED17 M959 1
D 5 DE92-50127H ASSY DOOR-E;COATING BLACK T0.8 1 WHITE/RED
D 5 DE92-50127F ASSY DOOR-E;BLK COATING DOOR-E/T0.8 1 GREEN
D 6 DE64-40012A DOOR-C;RESIN-PP(TB53) T2.0 CE945GF BLA 1
D 7 DE01-00002B FILM-DOOR;PC T0.15 275 175 MW5574W 1
D 8 DE61-70126A SPRING-KEY;0.8 0.36 6 BLUING 1 WHITE/RED
D 8 DE61-70032A SPRING-KEY;ES MSWR PI0.6 D5.4 L25 MW8640T 1 GREEN
D 9 DE64-40264A DOOR-KEY;POM(HANDLE) T.25 W51 L40 40G 1
D 10 DE61-80003A HINGE-LOWER;SCP1 T2.3 26 77 ZPC3 WHT CHR 1
D 11 DE61-80002A HINGE-UPPER;SCP1 T2.3 26 77 ZPC3 WHT CHR 1
D 12 DE92-40197A ASSY DOOR-A;M959 WHT 1 WHITE
D 12 DE92-40198A ASSY DOOR-A;M959C RED 1 RED
D 12 DE92-40198B ASSY DOOR-A;M959GR.XEF GRN 1 GREEN

Exploded Views and Parts List

7-3 Door Parts List

Parts No. Description / Specification Q'ty Remarks

DE60-10012A SCREW-TAP TITE;TH,+,3,M4,L10,SWR10,ZPC2,TOOTH 1 P-C-EA
DE60-10012A SCREW-TAP TITE;TH,+,3,M4,L10,SWR10,ZPC2,TOOTH 1 S-M-EA
DE60-10012A SCREW-TAP TITE;TH,+,3,M4,L10,SWR10,ZPC2,TOOTH 1 N-F-EA
DE60-10033A SCREW-TH;TH,+,M4,L10,MSWR10,FEFZY 2 HI-LOW
DE60-10033A SCREW-TH;TH,+,M4,L10,MSWR10,FEFZY 2 HI-UPP
DE60-10045A SCREW-TAP PH;PH,M3,L6,FEFZY 2 MG-TCO
DE60-10080A SCREW-WASHER;M5,L12,2S 4 TNS-HV
DE60-10080A SCREW-WASHER;M5,L12,2S 4 TNS-HV
DE60-10082H SCREW-A;2S-4X12,TOOTHED 5 PN/OUT
DE60-10082H SCREW-A;2S-4X12,TOOTHED 2 B-PLTE
DE60-10082H SCREW-A;2S-4X12,TOOTHED 2 BD-LAT
DE60-10082H SCREW-A;2S-4X12,TOOTHED 2 CN-BOX
DE60-10082H SCREW-A;2S-4X12,TOOTHED 1 CV/AIR
DE60-10082H SCREW-A;2S-4X12,TOOTHED 2 MO/FAN
DE60-10098A SCREW-ASSY TAP TITE;PH,TC,M4X8,SWRCH18A,ZPC2,GLD,W 1 CV-TCO
DE60-10098A SCREW-ASSY TAP TITE;PH,TC,M4X8,SWRCH18A,ZPC2,GLD,W 2 M/GEAR
DE60-10045A SCREW-TAP PH;PH,M3,L6,FEFZY 1
DE60-10066A SCREW-TAP TH;TH,M4,L8,FEFZY,2-SLOT 2 H/DOOR
DE60-10012A SCREW-TAP TITE;TH,+,3,M4,L10,SWR10,ZPC2,TOOTH 1 B/D-MO
DE60-10098A SCREW-ASSY TAP TITE;PH,TC,M4X8,SWRCH18A,ZPC2,GLD,W 1 B/HVC

7-4 Standard Parts List

7-4 Samsung Electronics

Exploded Views and Parts List

Ref. No Parts No. Description / Specification Q'ty Remarks

B 1 DE66-40021A LATCH-BODY;POM(F20-02) 50GR RE-330 1
B 2 3405-000178 SWITCH-MICRO;250V,15A,200gf,SPST-NO 2
B 3 3405-000175 SWITCH-MICRO;250V,15A,200gf,SPST-NO 1
B 4 DE66-90054A LEVER-SWITCH;POM(F20-02) 15G NTR RE-330 1

7-6 Body Latch Parts List

Ref. No. Parts No. Description/Specification Q'ty Remarks

C 1 DE71-60366F COVER-PANEL;ABS(HR0370U) 45G WHT M95 1 WHITE
C 1 DE71-60366G COVER-PANEL;ABS-HR0370 45G BLK M959C 1 RED
C 1 DE71-60366K COVER-PANEL;ABS(HR0370D) GRN M959GR/XEF 1 GREEN
C 2 DE67-40145A WINDOW-DISPLAY;ACRYL T2 W40 L77 SMOG 30G 1
C 3 DE72-70171G CONTROL-PANEL;ABS(HR0370U) WHT 160G M9 1 WHITE
C 3 DE72-70171H CONTROL-PANEL;ABS-HR0370 RED 160G M959 1 RED
C 3 DE72-70171Q CONTROL-PANEL;ABS GRN M959/XEF 1 GREEN
C 4 DE66-20174R BUTTON-SELECT-A;PC 2G WHT M959 1 WHITE
C 4 DE66-20174S BUTTON-SELECT-A;PC 2G WINE-RED M759C 1 RED
C 4 DE66-20174T BUTTON-SELECT-A;PC 2G DEEP-GRN M759GR 1 GREEN
C 5 DE66-20197J BUTTON-SELECT(A-B);PC 2G WHT M959 1 WHITE
C 5 DE66-20197K BUTTON-SELECT(A-B);PC 2G WINE-RED M759C 1 RED
C 5 DE66-20197L BUTTON-SELECT(A-B);PC 2G DEEP-GRN M759GR 1 GREEN
C 6 DE66-20198J BUTTON-SELECT(A-C);PC 2G WHT M959 1 WHITE
C 6 DE66-20198K BUTTON-SELECT(A-C);PC 2G WINE-RED M759C 1 RED
C 6 DE66-20198L BUTTON-SELECT(A-C);PC 2G DEEP-GRN M759GR 1 GREEN
C 7 DE66-20179A BUTTON-SELECT;ABS(HR0370) NTR 30G RE-445 1
C 8 DE91-10502A ASSY PCB-MAIN;RC-M959-00 230V50HZ LED M959 1
C 9 DE66-20175E BUTTON-SELECT-B;ABS(HR0370U) 5G, WHT M959 1 WHITE
C 9 DE66-20175D BUTTON-SELECT-B;ABS(HR0370) BLK 5G RE-446 1 RED
C 9 DE66-20175F BUTTON-SELECT-B;ABS(HR0370D) 5G GRN M959GR 1 GREEN
C 10 DE66-20176E BUTTON-SELECT-C;ABS(HR0370U) 5G, WHT M959 1 WHITE
C 10 DE66-20176D BUTTON-SELECT-C;ABS(HR0370) BLK 5G RE-446 1 RED
C 10 DE66-20176F BUTTON-SELECT-C;ABS(HR0370) 5G GRN M959GR 1 GREEN
C 11 DE66-20177E BUTTON-SELECT-D;ABS(HR0370U) 3G, WHT M959 1 WHITE
C 11 DE66-20177B BUTTON-SELECT-D;ABS(HR0370) RED 3G RE-445R 1 RED
C 11 DE66-20177F BUTTON-SELECT-D;ABS(HR0370D) 2G GRN M959GR/XEU 1 GREEN
C 12 DE66-20178E BUTTON-SELECT-E;ABS(HR0370U) WHT 2G M959 1 WHITE
C 12 DE66-20178B BUTTON-SELECT-E;ABS(HR0370) RED 3G RE-445R 1 RED
C 12 DE66-20178F BUTTON-SELECT-E;ABS(HR0370D) 2G GRN M959GR 1 GREEN
C 13 DE61-70126A SPRING-KEY;0.8 36 6 BLUING 1
C 14 DE66-20173E BUTTON-START;ABS(HR0370U) 7G WHT M959 1 WHITE
C 14 DE66-20173F BUTTON-START;ABS(HR0370) 7G RED M959C 1 RED
C 14 DE66-20173M BUTTON-START;ABS GRN M959GR/XEF 1 GREEN
C 15 DE93-30406G ASSY CONTROL-PANEL;M959 WHT 1 WHITE
C 15 DE93-30406H ASSY CONTROL-PANEL;240V50HZ M959C RED 1 RED
C 15 DE93-30406Q ASSY CONTROL-PANEL;230V50HZ M959GR/XEF GRN 1 GREEN

7-5 Control Parts List

8. P.C.B Diagrams

8-1 P.C.B Diagrams

Samsung Electronics 8-1

8-2 Samsung Electronics

Parts No. Description / Specification Q'ty Remarks

1003-001033 IC-SOURCE DRIVER;TD62781AP,DIP,18P,300MIL,OCTAL 1 IC02
3501-001050 RELAY-MINIATURE;24VDC,200mW,5A,1FormA,10mS,5mS 2 RY02,RY03
3501-001062 RELAY-POWER;24VDC,523.2mW,16A,1FormA,15mS 1 RY01
3710-000246 CONNECTOR-SOCKET;9P,1R,2.5mm,STRAIGHT,SN 1 CN05
DE07-20133A LED DISPLAY;ODG-404ADL,GRN,5,22,H24,RE-445 1 LED1
DE09-30650A IC-MCU;KS57C0004-G6E,4,DIP,4,-,M959 1 IC01
DE13-20016A IC-VOLT REGU;KA7805A,TO-220AB,1A,0/125C 1 IC04
DE26-20146A TRANS-L.V;SLV-745EN,230V,50HZ,AC17/7V 1 LVT1
DE30-20016A BUZZER;CBE2220BA,STICK 1 BUZ1
DE37-90019A CONNECTOR ASSY;YJN25009,PLATE,73MM,WHT 1 CN04
0401-001025 DIODE-SWITCHING;1N4148M,50V,450mA,DO-34,TP 10 D04~D13
0402-001188 DIODE-RECTIFIER;1T4(TP26),400V,1A,TS-1,TP 3 D1~03
0403-000717 DIODE-ZENER;MTZJ5.1B,5.1V,4.94-5.2V,500mW 1 ZD01
0501-000283 TR-SMALL SIGNAL;KSA539,PNP,400mW,TO-92,TP,120 1 TR03
0501-000388 TR-SMALL SIGNAL;KSC815,NPN,400mW,TO-92,BK,120 2 TR01,TR04
0504-001014 TR-DIGITAL;KSR1005,NPN,300mW,4.7K-10K,TO 4 TR02,TR05,TR06,TR08
2001-000273 R-CARBON;100Kohm,5%,1/8W,AA,TP,1.8x3.2m 1 R15
2001-000290 R-CARBON;10Kohm,5%,1/8W,AA,TP,1.8x3.2mm 9 R05~R07,R10,R12,R13,R19~R21
2001-000429 R-CARBON;1Kohm,5%,1/8W,AA,TP,1.8x3.2mm 5 R01,R02,R08,R11,R17
2001-000502 R-CARBON;20ohm,5%,1/4W,AA,TP,2.4x6.4mm 7 R22~R28
2001-000577 R-CARBON;2Kohm,5%,1/8W,AA,TP,1.8x3.2mm 2 R03,04
2001-000613 R-CARBON;3.9Kohm,5%,1/8W,AA,TP,1.8x3.2m 3 R09,R14,R16
2001-000904 R-CARBON;620ohm,5%,1/8W,AA,TP,1.8x3.2mm 1 R18
2202-000780 C-CERAMIC,MLC-AXIAL”;100nF,+80-20%,50V,Y5V,TP,3.5x1 4 C05~C08
2401-000247 C-AL;100uF,20%,10V,GP,-,6.3x11mm,5m 1 C03
2401-000876 C-AL;220uF,20%,50V,GP,TP,13x20mm,5m 1 C01
2401-000914 C-AL;22uF,20%,16V,-,TP,5x11,5mm 1 C04
2401-001362 C-AL;470uF,20%,16V,GP,-,10x12.5mm,5 1 C02
2802-000161 RESONATOR-CERAMIC;4MHz,0.5%,TP,10.0x5.0x7.5mm 1 XTL1
3404-000282 SWITCH-TACT;12Vdc,50mA,120+-30gf,6.2x3.6mm 10 SW01~SW10
3711-000203 CONNECTOR-HEADER;1WALL,3P,1R,3.96mm,ANGLE,SN 1 CN01
3711-000240 CONNECTOR-HEADER;1WALL,4P,1R,3.96mm,STRAIGHT,SN 1 CN02
3711-000881 CONNECTOR-HEADER;BOX,3P,1R,2.5mm,STRAIGHT,SN 1 CN03
DE13-20009A IC;KA7533,DIP 1 IC03
DE39-60001A WIRE-SO COPPER;PI0.6,SN,T,52MM,TAPING_WIRE 10 J01~J10
DE60-60012A PIN-EYELET;ID2.1,OD2.5,L3.0,SN,BSP,T0.25 6

8-2 P.C.B Parts List

P.C.B Diagrams

9. Schematic Diagrams

9-1 Schematic Diagrams

9-1

230V~
50Hz

VOLTAGE
FREG

BRN

BRN

BRN BRN BLK

BLU

BLU

BLK

YELYEL

YEL

YEL

ORG

ORG

ORG

BLU

BLU

0V

21V

230V

WHT

BLU

500K

2200pFC2 C12200pF

LIN-CAPACITORT 0.1uF

E

E

ASSY NOISE FILTER

MGT

TCO

CAVITY

TCO

MONITOR

FUSE

PRIMARY

SWITCH

INRUSH RELAY

MONITOR

SWITCH

L.V.T

MAIN

RELAY

POWER

RELAY

INRUSH

RELAY

DOOR

SENSING

SWITCH

DOOR

SENSING

SWITCH

RESISTOR

POWER RELAY

MAIN

RELAY

F FA

MAGNETRON

NO

COM

NO

NO

BLU YEL

BRN

BRN

BRN BLK

BLU BLK

COM

0V

LAMP

(230V40W)

L.V.TRANS

PRIMARY
LATCH
SWITCH

NO

COM

ORG

ORG

MONITOR
SWITCH

L

FM

H.V.T

H.V.D

H.V.C

H.V.FUSE

1mH

BRN BROWN
BLU BLUE
ORG ORANGE
RED RED
WHT WHITE
BLK BLACK
YEL YELLOW
GRN GREEN
Y/G YELLOW/GREEN

SYMBOL COLOR

NOTE

MAIN FUSE

DM

1. INPUT : 230V

2. DOOR : OPEN

3. LAMP : ON

4. : P.C.B PATTERN

5. : P.C.B IN/OUT
POINT

ASSY MAIN P.C.B

Samsung Electronics