Daewoo KOR-1A7G9T(AKM3180S), KOR-1A7G, KOR-1A7G9T, AKM3180S Service Manual

Service Manual

Microwave Oven

Model: KOR-1A7G9T(AKM3180S)

S/M No. : R1A7G9T001

April. 2005

✔Caution

: In this Manual, some parts can be changed for improving,

their performance without notice in the parts list. So, if you
need the latest parts information, please refer to PPL(Parts
Price List) in Service Information Center (http://svc.dwe.co.kr).

1

PRECAUTIONS TO BE OBSERVED BEFORE AND
DURING SERVICING TO AVOID POSSIBLE
EXPOSURE TO EXCESSIVE MICROWA VE ENERGY

(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 micro-

wave 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 power to the microwave oven for any service test or inspection within the microwave gen-

erating 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 per-

formed on each oven prior to release to the owner.

T ABLE OF CONTENTS

SAFETY AND PRECAUTIONS...........................................................................................................................................2

1. FOR SAFE OPERATION ..................................................................................................................................2

2. FOR SAFE SERVICE PROCEDURES .............................................................................................................2

SPECIFICATIONS...............................................................................................................................................................3

EXTERNAL VIEW................................................................................................................................................................4

1. OUTER DIMENSION.........................................................................................................................................4

2. FEATURE DIAGRAM........................................................................................................................................5

3. CONTROL PANEL............................................................................................................................................6

INSTALLATION...................................................................................................................................................................7

OPERATIONS AND FUNCTIONS.......................................................................................................................................8

DISASSEMBLY AND ASSEMBLY......................................................................................................................................9

INTERLOCK MECHANISM AND ADJUSTMENT.............................................................................................................16

TROUBLESHOOTING GUIDE ..........................................................................................................................................17

MEASUREMENT AND TEST............................................................................................................................................21

1. MEASUREMENT OF THE MICROWAVE POWER OUTPUT ........................................................................21

2. MICROWAVE RADIATION TEST...................................................................................................................22

3. COMPONENT TEST PROCEDURE...............................................................................................................23

WIRING DIAGRAM............................................................................................................................................................24

PRINTED CIRCUIT BOARD..............................................................................................................................................25

1. CIRCUIT CHECK PROCEDURE ....................................................................................................................25

2. PCB CIRCUIT DIAGRAM................................................................................................................................28

3. P.C.B. LOCATION NO ....................................................................................................................................29

EXPLODED VIEW AND PARTS LIST...............................................................................................................................30

1. DOOR ASSEMBLY .........................................................................................................................................30

2. CONTROL PANEL ASSEMBLY......................................................................................................................30

3. TOTAL ASSEMBLY.........................................................................................................................................30

2

SAFETY AND PRECAUTIONS

1. FOR SAFE OPERATION

Damage that allows the microwave energy (that cooks or heats the food) to escape will result in poor cooking and may
cause serious bodily injury to the operator.
IF ANY OF THE FOLLOWING CONDITIONS EXIST, OPERATOR MUST NOT USE THE APPLIANCE.
(Only a competent service personnel should make repairs.)

(1) A broken door hinge.
(2) A broken door viewing screen.
(3) A broken front panel, oven cavity.
(4) A loosened door lock.

(5) A broken door lock.
The door gasket plate and oven cavity surface should be kept clean.
No grease, soil or spatter should be allowed to build up on these surfaces or inside the oven.
DO NOT ATTEMPT TO OPERATE THIS APPLIANCE WITH THE DOOR OPEN.
The microwave oven has concealed switches to make sure the power is turned off when the door is opened.
Do not attempt to defeat them.
DO NOT ATTEMPT TO SERVICE THIS APPLIANCE UNTIL YOU HAVE READ THIS SERVICE MANUAL.

2. FOR SAFE SERVICE PROCEDURES

1. If the oven is operative prior to servicing, a microwave emission check should be performed prior to servicing the

oven.

2. If any certified oven unit is found to have excessive emission level 5mw/cm

2

, the service person should:
(a) inform the manufacturer, importer or assembler,
(b) repair the unit at no cost to the owner,
(c) attempt to ascertain the cause of the excessive leakage,
(d) tell the owner of the unit not to use the unit until the oven has been brought into compliance.

3. If the oven operates with the door open, the service person should tell the user not to operate the oven and contact
the manufacturer and CDRH immediately.

CAUTION

This device is to be Serviced only by Properly Qualified Service Personel. Consult the Service Manual for Proper
Service Procedures to Assure Continued Safety Operation and for Precautions to be Taken to Avoid Possible
Exposure to Excessive Microwave Energy.

CAUTION

MICROWAVE RADIATION
PERSONNEL SHOULD NOT BE EXPOSED TO THE MICROWAVE ENERGY WHICH MAY RADIATE FROM

THE MAGNETRON OR OTHER MICROWAVE GENERATING DEVICE IF IT IS IMPROPERLY USED OR
CONNECTED. ALL INPUT AND OUTPUT MICROWAVE CONNECTIONS. WAVEGUIDE FLANGES AND
GASKETS MUST BE SECURE. NEVER OPERATE THE DEVICE WITHOUT A MICROWAVE ENERGY
ABSORBING LOAD ATTACHED. NEVER LOOK INTO AN OPEN SAVEGUIDE OR ANTENNA WHILE THE
DEVICE IS ENERGIZED.

3

MODEL KOR-1A7G9T (AKM3180S)
POWER SUPPLY 110V-60Hz, SINGLE PHASE WITH EARTHING

MICROWAVE 1400W

POWER CONSUMPTION GRILL

COMBINATION
MICROWAVE ENERGY OUTPUT 1000W
MICROWAVE FREQUENCY 2450MHz
OUTSIDE DIMENSIONS (W X H X D) 539 x 300 x 431mm (21.2 x 11.8 x 16.1 in)
CAVITY DIMENSIONS (W X H X D) 354 x 228 x 373 mm (13.9 x 9 x 14.7 in)
NET WEIGHT APPROX. 15.8 kg (34.9 Ibs.)
TIMER 99 min. 99 sec.
FUNCTION SELECTIONS MICROWAVE
POWER SELECTIONS 10 LEVELS
CAVITY VOLUME 31 L

* SPECIFICATIONS ARE SUBJECT TO CHANGE WITHOUT NOTICE.

SPECIFICATIONS

4

EXTERNAL VIEW

1. OUTER DIMENSION

5

11

DOOR HOOK

When the door is closed, it will automatically lock shut. If door is opened while oven is operating, magnetron tube will
immediately stop operating.

22

DOOR SEAL

Door seal maintains the microwave within the oven cavity and prevents microwave leakage.

33

OVEN CAVITY

44

OVEN LAMP

Automatically turns on during oven operating.

55

SAFETY INTERLOCK SYSTEM

66

CONTROL PANEL

77

SPATTR SHIELD

Protects the microwave outlet from splashes of cooking foods.

88

GLASS COOKING TRAY

Made of special heat resistant glass. The tray must always be in proper position before operating. Do not cook food
directly on the tray.

99

COUPLER

This fits over the shaft in the center of the oven cavity floor.
This is to remain in the oven for all cooking.

00

ROLLER GUIDE

Supports the glass cooling tray.

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DOOR SCREEN

Allows viewing of food. Microwave cannot pass through perforations in screen.

2. FEA TURE DIAGRAM

6

1

2

3
4

5

6

7

8

w

q

0

9

11

DISPLAY - Cooking time, power level, indicators and the current time are displayed.

22

AUTO COOK - Used to cook or reheat many of favorite food.

33

ONE TOUCH COOK - Used to cook or reheat specific quantities of food.

44

+, - - Used to add or decrease time for cooking.

55

AUTO DEFROST - Used to defrost foods.(for weight defrost)

66

POWER - Used to set power level.

77

DEFROST - Used to defrost foods for time.

88

STOP/CLEAR - Used to stop the oven operation or to delete the cooking data.

99

TIME SET PAD - Used to set the cooking time and the current time.

00

CLOCK - Used to set clock.

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KITCHEN TIMER - Used as a minute timer, to delay the start of cooking, or to set a holding time after cooking.

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START/SPEEDY COOK - Used to start the oven and also used to set a reheat time.

3. CONTROL P ANEL

7

INSTALLA TION

1. Steady, flat location.

This microwave oven should be set on a steady, flat surface.

2.Leave space behind and side.

All air vents should be kept a clearance. If all vents are covered during operation, the oven may be overheated
and, eventually, cause oven failure.

3.Away from radio, and TV sets

Poor television reception and radio interference may result if the oven is located close to a TV, radio, antenna, or
feeder and so on.

4.Away from heating appliances and water taps

Keep the oven away from hot air, steam or splash when choosing a place to position it, or the insulation might be
adversely affected and breakdowns occur.

5.Power supply

• Check your local power source.
This microwave oven requires a current of approximately 20 amperes, 110Volts, 60Hz grounded outlet.

• Power supply cord is about 1.0 meters long.

1. A short power-supply cord is provided to reduce the risks resulting from becoming entangled in or tripping over

a longer cord.

2. Longer cord sets or extension cords are available and may be used if care is exercised in their use.

3. If a long cord or extension cord is used:

1) The marked electrical rating of the cord set or extension cord should be at least as great as the electrical rat­ing of the appliance.

2) The extension cord must be a grounding type 3-wire cord.

3) The longer cord should be arranged so that it will not drape over the counter top or tabletop where it can be
pulled on by children or tripped over unintentionally.

6. Examine the oven after unpacking for any damage such as:

A misaligned door, broken door or a dent in cavity.
If any of the above are visible, DO NOT INSTALL, and notify dealer immediately.

8

Make sure the oven is properly installed and plugged into the electrical.

OPERATIONS AND FUNCTIONS

1. Connect the mains lead to an electrical outlet.

2. After placing the food in a suitable container, open the oven door and put it on the glass tray. The glass tray must always
be in place during cooking.

3. Close the door securely.

4. When the oven door is opened, the light turns on.

5. The oven door can be opened at any time during operation by pushing the door release button on the control panel.

The oven will automatically shut off. To restart the oven, close the door and then touch START pad.

6. Each time a pad is touched. a BEEP will sound to acknowledge the touch.

7. The oven automatically cook on full power unless set to a lower power level.

8. The display will show : 0 when the oven is plugged in.

9. Time clock returns to the present time when the cooking time ends.

10. When the STOP/CLEAR pad is touched during the oven operation, the oven stops cooking and all information retained.

To erase all information (except the present time), touch the STOP/CLEAR pad once more. If the oven door is opened
during the oven operation, all information is retained.

11. If the START pad is touched and the oven does not operate, check the area between the door and door is closed

securely. The oven will not start cooking under the door is completely closed or the program has been reset.

Wattage output chart

The power level is set by touching the POWER pad. The chart shows the display, the power level and the percentage
of power.

Touch POWER Pad

Once

Twice
3 times
4 times
5 times
6 times
7 times
8 times
9 times

10 times
11 times

Power Level(Display)

P-HI
P-90
P-80
P-70
P-60
P-50
P-40
P-30
P-20
P-10
P-00

Approximate Percentage of Power

100%

90%
80%
70%
60%
50%
40%
30%
20%
10%
00%

9

DISASSEMBLY AND ASSEMBL Y

Cautions to be observed when troubleshooting.

Unlike many other appliances, the microwave oven is high-voltage, high-current equipment.
It is completely safe during normal operation.
However, carelessness in servicing the oven can result in an electric shock or possible danger from a short circuit.
You are asked to observe the following precautions carefully.

1. Always remove the power plug from the outlet before servicing.

2. Use an insulated screwdriver and ware rubber gloves when servicing the high voltage side.

3. Discharge the high voltage capacitor before touching any oven components or wiring.

(1) Check the grounding.

Do not operate on a two-wire extension cord.
The microwave oven is designed to be used while earthed.
It is imperative, therefore, to make sure it is earthed
properly before beginning repair work.

(2) Warning about the electric charge in the high voltage capacitor.

For about 30 seconds after the operation stopped and electric
charge remains in the high voltage capacitor.
When replacing or checking parts, short between oven chassis and
the negative high terminal of the high voltage capacitor by using a
properly insulated screwdriver to discharge.

4. When the 20A fuse is blown out due to the operation of the monitor
switch; replace primary interlock switch, secondary interlock switch and
interlock monitor switch.

5. After repair or replacement of parts, make sure that the screws are
properly tightened, and all electrical connections are tightened.

6. Do not operate without cabinet.

CAUTION : Service personnel should remove their watches whenever working close to or replacing the magnetron.

WARNING :When servicing the appliance, need a care of touching or replacing high potential parts because of

electrical shock or exposing microwave. These parts are as follows - HV Transformer, Magnetron,
HV Capacitor, HV Diode, HV fuse.

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