LG 21FS2CG, 21FS2CL, 21FS2CL-TS, 21FS2CG-TS Service Manual

COLOR TV

SERVICE MANUAL

CAUTION

BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

CHASSIS : MC-059C

MODEL : 21FS2CG/CL

MODEL :

21FS2CG/CL-TS

website:http://biz.LGservice.com

e-mail:http://www.LGEservice.com/techsup.html

- 2 -

CONTENTS

CONTENTS............................................................................................................. 2

SAFETY PRECAUTIONS....................................................................................3

DESCRIPTION OF CONTROLS.......................................................................4

SPECIFICATIONS ..................................................................................................7

ADJUSTMENT........................................................................................................9

PRINTED CIRCUIT BOARD .............................................................................16

TROUBLE SHOOTING.......................................................................................18

BLOCK DIAGRAM ..............................................................................................22

EXPLODED VIEW................................................................................................24

EXPLODED VIEW PARTS LIST.....................................................................25

REPLACEMENT PARTS LIST ....................................................................... 26

- 3 -

SAFETY PRECAUTIONS

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in
the Schematic Diagram and Replacement Parts List.
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to
prevent X-RADIATION, Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.

General Guidance

An isolation Transformer should always be used during
the servicing of a receiver whose chassis is not isolated from
the AC power line. Use a transformer of adequate power rating
as this protects the technician from accidents resulting in
personal injury from electrical shocks.

It will also protect the receiver and it's components from being
damaged by accidental shorts of the circuitry that may be
inadvertently introduced during the service operation.

If any fuse (or Fusible Resistor) in this TV receiver is blown,
replace it with the specified.

When replacing a high wattage resistor (Oxide Metal Film
Resistor, over 1W), keep the resistor 10mm away from PCB.

Keep wires away from high voltage or high temperature parts.

Due to high vacuum and large surface area of picture tube,
extreme care should be used in handling the Picture Tube.
Do not lift the Picture tube by it's Neck.

X-RAY Radiation

Warning:

To determine the presence of high voltage, use an accurate
high impedance HV meter.

Adjust brightness, color, contrast controls to minimum.
Measure the high voltage.
The meter reading should indicate

23.5

¡ 1.5KV: 14-19 inch, 26 ¡ 1.5KV: 19-21 inch,

29.0 ¡ 1.5KV: 25-29 inch, 30.0 ¡ 1.5KV: 32 inch
If the meter indication is out of tolerance, immediate service
and correction is required to prevent the possibility of
premature component failure.

Before returning the receiver to the customer,

always perform an AC leakage current check on the exposed
metallic parts of the cabinet, such as antennas, terminals, etc.,
to be sure the set is safe to operate without damage of
electrical shock.

Leakage Current Cold Check(Antenna Cold Check)

With the instrument AC plug removed from AC source,
connect an electrical jumper across the two AC plug prongs.
Place the AC switch in the on position, connect one lead of
ohm-meter to the AC plug prongs tied together and touch other
ohm-meter lead in turn to each exposed metallic parts such as
antenna terminals, phone jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1MΩ and 5.2MΩ.
When the exposed metal has no return path to the chassis the
reading must be infinite.
An other abnormality exists that must be corrected before the
receiver is returned to the customer.

Leakage Current Hot Check (See below Figure)

Plug the AC cord directly into the AC outlet.

Do not use a line Isolation Transformer during this check.

Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Measure the AC voltage across the resistor using AC
voltmeter with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC
voltage measurements for each exposed metallic part. Any
voltage measured must not exceed 0.75 volt RMS which is
corresponds to 0.5mA.
In case any measurement is out of the limits specified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.

Leakage Current Hot Check circuit

The source of X-RAY RADIATION in this TV receiver is the
High Voltage Section and the Picture Tube.
For continued X-RAY RADIATION protection, the
replacement tube must be the same type tube as specified in
the Replacement Parts List.

1.5 Kohm/10W

To Instrument’s
exposed
METALLIC PARTS

Good Earth Ground
such as WATER PIPE,
CONDUIT etc.

AC Volt-meter

IMPORTANT SAFETY NOTICE

0.15uF

All the functions can be controlled with the remote control handset.
Some functions can also be adjusted with the buttons on the front
panel of the set.

Remote control handset

Before you use the remote control handset, please install the bat­teries. See the next page.

1. POWER

switches the set on from standby or off to standby.

2. NUMBER BUTTONS

switches the set on from standby or directly select a number.

3. MENU (or INDEX)

selects a menu.
selects an index page in the teletext mode (only TELETEXT
models). (option)

4. EYE/

*

(option)

switches the eye function on or off.

5.

DD/ EE

(Programme Up/Down)

selects a programme or a menu item.
switches the set on from standby.
scans programmes automatically.

FF/ GG

(Volume Up/Down)

adjusts the volume.
adjusts menu settings.

OK

accepts your selection or displays the current mode.

6. Q.VIEW

returns to the previously viewed programme.

7. PSM (Picture Status Memory)

recalls your preferred picture setting.

8. FAVOURITE

selects a favorite programme.

9. TURBO PICTURE / SOUND BUTTON (option)

selects Turbo picture and sound.

POWER MUTE

123

456

789

MENU/INDEX

TV/AV

0

EYE/

Q.VIEW

LIST

I / II /

( )

PR

( )

PR

OK

VOLVOL

PSM SSM/ SLEEP

PICTURE SOUND

/

TURBO/

FAVOURITE

TV

1

2

3
4

5

6

7

9

8

- 4 -

DESCRIPTION OF CONTROLS

- 5 -

10. MUTE

switches the sound on or off.

11. TV/AV

selects TV or AV mode.
switches the set on from standby.

12. I/II/

*

(option)

selects the language during dual language broadcast. (option)
selects the sound output.

13. LIST

displays the programme table.

14. SLEEP

sets the sleep timer.

15. SSM/

*

(Sound Status Memory) (option)

recalls your preferred sound setting.

16. SURROUND (ºº/

*

) (option)

selects surround sound.

*

: No function

COLOURED BUTTONS : These buttons are used for teletext (only

TELETEXT models) or programme edit.

POWER MUTE

1 2 3

4 5 6

7 8 9

MENU/INDEX

TV/AV

0

EYE/

Q.VIEW

LIST

I / II /

( )

PR

( )

PR

OK

VOLVOL

PSM SSM/ SLEEP

PICTURE SOUND

/

TURBO/

FAVOURITE

TV

10

11
12

13

14
16

15

- 6 -

Front panel

Side panel

1. MAIN POWER (ON/OFF)

switches the set on or off.

2. POWER/STANDBY INDICATOR

illuminates brightly when the set is in standby mode.
dims when the set is switched on.

3. REMOTE CONTROL SENSOR

Note : Only use the supplied remote control handset. (When you use others, they’ll be not able to

function.)

4. MENU

selects a menu.

5. OK

accepts your selection or displays the current mode.

FF / GG

(Volume Up/Down)

adjusts the volume.
adjusts menu settings.

DD / EE

(Programme Up/Down)

selects a programme or a menu item.
switches the set on from standby.

6. AUDIO/VIDEO IN SOCKETS (AV IN2) (option)

Connect the audio/video out sockets of external equipment to these sockets.

7. HEADPHONE SOCKET (option)

Connect the headphone plug to this socket.

Note : Shown is a simplified representation of front or side panel. Here shown may be somewhat dif­ferent from your set.

VIDEO

L/MONO

R

AUDIO

AV IN2

7

6

1 2 3 4 5

V Scope

This specification is applied to all the television related to MC­059C Chassis.

V Requirement for Test

Each part is tested as below without special appointment.

1) Temperature : 25 ± 5°C (77 ± 9°F), CST : 40 ± 5
(CST must be tested 40

± 5°C . Humidity : 50%)

2) Relative Humidity : 65

± 10%

3) Power Voltage : Standard input Voltage (AC110-240V~,
50/60Hz)
* Standard Voltage of each products is marked by models.

4) Specification and performance of each parts are followed
each drawing and specification by part number in
accordance with BOM.

5) The receiver must be operated for about 20 minutes prior to
the adjustment.

V Test Method

1) Performance : LGE TV test method followed.

2) Demanded other specification

- CCC

- Safety : K60065

- 7 -

A General specification

SPECIFICATIONS

Note : Specification and others are subject to change without notice for improvement.

Item

Receiving System

Available Channel

Input Voltage
Market
Screen Size
Aspect Ratio
Display Method
Tuning System
Operating Environment

Storage Environment

Specification

PAL BG, DK, I / NTSC M (AV 3.58/ 4.43)
SECAM DK
VHF : E2 ~ E12
UHF : E21 ~ E69
CATV : S1 ~ S20
HYPER : S21 ~ S41
AC100 - 240V~, 50/60Hz
China, Indonesia, Thai, Vietnam, CIS
14 ~ 21inch (FLAT / Conventional)
4:3
CRT
FVS
Temp : 0 ~ 40 deg
Humidity : ~ 85 %
Temp : -20 ~ 60 deg
Humidity : ~ 90 %

Remark

China/ Indonesia/ Thai/ Vietnam
CIS

No.

1

2

3
4
5
6
7
8
9

10

- 8 -

A Features and Function

Item

Feature AV Input

AV Output
Component
Earphone

Key Local Key

Remocon

Channel Auto prog.

Manual
Prog. edit
Favorite

Picture PSM

User Control

Sound SSM

Treble/ Bass
Equalizer
FM Transmitter

Timer Clock

Off time
On time
Auto off

Special Language

Input
Child lock

Etc. Sleep

Review

Specification

2 AV 1, 2
1 Monitor out

Input(For component)

1 Front

Power, Vol(

F , G ), PR(E , D ), MENU, OK

Turbo-Picture, Sound
LG Code (NEC)
System/ Storage/ Normal/ Turbo
Storage/ System/ Channel/ Fine/ Search/ Name
Copy/ Move/ Delete/ Skip
8 Channel
Dynamic/ Standard/ Mild/ Game/ User
Contrast/ Brightness/ Color/ Sharpness
Tint (NTSC-M Only)
Flat/ Music/ Movie/ Speech/ User
0 ~ 100
100/ 400/ 1K/ 4K/ 10K
Low Band(7ch)

87.7/ 87.9/ 88.1/ 88.3/ 88.5/ 88.7/ 88.9(MHz)
High Band(7ch)

106.7/ 106.9/ 107.1/ 107.3/ 107.5/ 107.7/

107.9(MHz)
Wide Range(1091ch)

88.0 ~ 107.0MHz

-- : --

-- : -- Off(On)

-- : -- Pr 1 VOL 30 Off(On)
On/ Off
Chinese/ English
English/ Russia
English/ Indonesia/ Thai/ Vietnam
TV/ AV1/ AV2/ Component
On/ Off

Remark

Rear1, Front1(CVBS,L,R)
Rear
Rear(Y,Pb,Pr,DVD-L/R)

7EA/ Front
Option

AV, RF Stereo Option
AV Stereo
RF Stereo

China
CIS
East-Asia

No.

1

2

3

4

5

6

7

8

1. Scope of Application

These instructions are applied to MC-059C Chassis.

2. Notes

1) Because this is a cold chassis, it is not necessary to use an
isolation transformer. However, operating it using a
transformer between the power supply line and chassis input
to prevent electric shock and to protect the test instrument.

2) All adjustment must be done in the correct sequence.
However, for better productivity, it can be change in a pre­permitted range.

3) Environment conditions : If not specified, it must be done in
following conditions.
Temperature : 25 ± 5°C
Humidity 60% ± 10%

4) Power supply of SET : AC100-240~ ± 10%, 50/60Hz

5) If not specified, the receiver must be operated for more than
20 minutes prior to the adjustment.

6) Signal : Received the standard color signal (65±1dBuV).

- NTSC

: LG standard signal means the digital pattern 13CH(480NC)

- PAL/SECAM

: LG standard signal means the digital pattern PAL-B/G 05CH

7) If not specified, APC ON is APC CLEAR(DYNAMIC)

3. AGC Voltage Adjustment

3-1. Necessary Instrument

: Digital Multi-meter-1 set

- Max Input Current : Over 1A/ Max Input Voltage : 500Vdc

- Measurement Range : 10mV-100mVdc/ Accuracy : 0.03%

3-2. Adjustment Preparation

1) Input in the 75Ω cable 65dB(±1dB) LG standard signal.

2) Connect the multi-meter to J105(AGC Check, Marking).

3-3. Adjustment

1) Press the “INSTART” key of factory remote control and

select “VP0 (RFAGC)” adjustment mode.

2) Press the VOL+/-(

F / G ) key until the multi-meter shows

reading as shown below.

3) CAUTION

: Since the signal strength can be easily changed by the

condition of signal cable, you need to check the signal
strength frequently in order to prevent error.

4. Screen Voltage Adjustment

4-1. Adjustment of Screen Manually

(Using SVC Remote Control)

1) Input in the 75ohm cable LG standard signal(Digital Pattern,
480NC).

2) Press the “ADJ’ key of factory remote control once to make
the TV set display.

3) Turn the screen volume on the FBT clockwise until the
horizontal line is visible and turn it counterclockwise until
horizontal line faintly visible.
(Exit screen voltage adjustment by press “Enter(

A )” key of

factory remote control.)

5. Purity and Convergence Adjustment

5-1. Purity adjustment

(1) Adjustment Preparation

1) Receive Red Raster Pattern for purity adjustment(51CH).

2) Demagnetize the CPT and Cabinet with a degaussing coil.

(2) Adjustment

1) Pre-adjust the static convergence (STC) with the 4 and

6pole magnet.

2) If the horizontal Line is inline with CPT Mark, 2-Pole

magnet should direct 3-9 o’clock direction.

3) If not, direct 2-pole magnet handle toward 6-12 o’clock

direction and adjust the Horizontal Line to fall onto the
mark opening the magnet at an angle.

4) Push the DY(deflection yoke) all the way to the CPT

funnel.

5) Turn the purity magnet(2-pole magnet) so that the “green”

color portion of left side and the “blue” color portion on the
right side have equal amount of color.

6) Pull the DY slowly backward and fix it when the whole

screen becomes red.
(The specified torque for fixing DY screw should be
10Kg/cm.)

5-2. Convergency Adjustment

(1) Necessary Instrument

1) Degaussing Coil

2) Convergency fixing instrument

(2) Preliminary steps

1) Operate the unit at the least 30minutes before adjustment.

2) Using degaussing coil, remove the stains on CPT &

Cabinet.

3) Received the Cross Hatch Pattern of Convergence.(09ch)

4) Let the Contrast in normal luminance level

.

G R B

- 9 -

ADJUSTMENT

G R B

R

G R B

6700VS0002F
6700PF0002F
6700MF0014A
6700MF0014B

LGIT

SANYO

LGIT
LGIT

3.0 ± 0.05V

2.3 ± 0.05V

2.3 ± 0.05V

2.15 ± 0.05V

70dBu
65dBu
65dBu
65dBu

TAEW-G002D

115-B-A86EL
TAEW-G013D
TAEW-G017D CIS

Tuner P/N Maker AGC Vol Signal Tuner Spec. Remark

- 10 -

(3) Static Convergence (STC) Adjustment

1) Receive the Cross Hatch Pattern Convergence(09ch).

2) Before adjusting Static Convergence(STC), adjust the
focus first seeing to it that the WHITE color picture quality
is sharp enough.

3) Converge the RED vertical and BLUE vertical line in
unity(same line) by changing the angle between the 2
tabs of 4-pole magnet.

4) Converge the RED horizontal and BLUE horizontal line in
unity(same line) by turning the 2 tabs of the 4-pole
magnet. At this time, do not change the angle between
the 2 tabs.

5) Converge the R, G, B vertical line in unity(same line) by
changing the angle between the 2 tabs of the 6-pole
magnet.

6) Converge the R, G, B horizontal line in unity(same line) by
turning the 2 tabs of the 6-pole magnet. At this time, do
not change the angle between the 2 tabs.

(4) Dynamic Convergence (DYC) Adjustment

1) Y-axis Adjustment

: Adjust convergence of Y-axis(vertical) by moving the

deflection yoke(DY) left and right.

2) X-axis Adjustment

: Adjust convergence of X-axis(horizontal) by moving the

deflection yoke(DY) up and down.

6. White Balance Adjustment

6-1. Necessary Instrument

1) Automatic White Balance Meter(Low/High light Pattern
generator)

2) White Balance meter(CRT Color Analyzer, CA-100) :1set

3) Factory Remote Control

6-2. Adjustment Preparation

: Prior to this adjustment, the Screen Voltage adjustment

should be finished.

6-3. Automatic adjustment

1) Adjust the using Auto White Balance Meter.

2) Enter CPU OFF Mode by pressing “IN-START” & “MUTE”
key of factor remote control in turn before adjustment.
Exit CPU OFF mode by press the “TV/AV” key of factory
remote control after adjustment finished.

* In case there is excess RED color at screen voltage

adjustment, adjust it using “volume - (

F ) key of factory remote

control until the RED color disappear.

6-4. Manual adjustment

1) Adjust using white Balance meter and factory remote
control.

2) Enter white balance adjustment mode by pressing
“INSTART” key

3) Use the CH

D , CHE Key to choose adjustment item.

4) Use the VOL

F , VOLG Key to change item data.

5) Adjustment Procedure
a. Make the picture luminance 45Ft-L by changing the

“CONTRAST” and “BRIGHTNESS”.

b. Adjust X data of High light with R-DRIVE(VP7) and Y

data with B-DRIVE(VP9) to have the color temperature
as shown below.

c. Make the picture luminance 4.5Ft-L by changing the

“CONTRAST” and “BRIGHTNESS”.

d. Adjust X data of low light with R-BIAS(VP4) and Y data

with B-BIAS(VP6) to have the color temperature as
shown below.

e. Repeat steps a~d until both low and high light have

same readings as shown below.

7. Focus Voltage Adjustment

This adjustment must be done after operating the TV set
receiver sufficiently.

7-1. Adjustment Preparation

1) Receive Digital pattern and Set the picture condition on
“APC ON”(CLEAR) mode.

7-2. Adjustment

Turn the focus volume on the FBT upper direction th have
the best focus vertical line(figure 1.(a)) and horizontal line
(figure 1(b)) as shown below.

8. SUB-BRIGHTNESS Adjustment

This adjustment must be done after White balance adjustment.

8-1. Adjustment Preparation

1) Receive the LG standard Mono scope pattern(CH14).

2) Set the picture condition on “APC ON”(CLEAR) mode.

8-2. Adjustment

1) Press the “ADJ”key of the factory remote control twice to
enter to “SUB-BRIGHTNESS” adjustment mode.

2) Change the Sub-Brightness data by pressing the VOL

F ,

VOL

G key so that the number 1 in gray scale of mono

scope pattern almost disappear.(See figure 2)

8-3. Sub-Tint adjustment

This adjustment has to be done only if the picture has bad tint
otherwise, it can be omitted if the picture has good tint.

1) Receive LG standard pattern signal(SMPTE, 2CH)

2) Set the picture condition on “APC ON”(CLEAR) mode.

Market Color Temperature X-AXIS Y-AXIS

PAL/SECAM 12,000±800 0.270±0.003 0.283±0.003

<Fig. 1>

<Fig. 2> MONO SCOPE Pattern signal

0 1 2 3 4 5 6 7 8 9

Gray Scale

Color Bar