Daewoo DLT-42GUL1 Schematic

Service Manual

LCD TV

CHASSIS : SL-701T

Model : DLT - 42U1GMB
DLT - 42G1LTBD
DLT - 46U1UMB
DLT - 46U1STB

S/M NO. : DSL701TEF0

Dec. 2007

Contents

1.Safety Precaution ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 3

2.Product Specification ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 4
2-1.Product Specification⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 4
2-2.Available Input Signal ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 5

3.Block Diagram ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 8
3-1.Signal Block Diagram ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 8
3-2.Power Tree ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 9

4.SERVICE MODE ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 10
4-1.EEPROM initial DATA ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 10
4-2.Description of SERVICE MODE ITEM ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 12

5.Trouble Shooting ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 13
5-1.No Signal⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 13
5-2.When No Sond ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 20
5-3.When Key does not operte ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 20
5-4.Facts you must know when trouble diagnosing or repairing ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 21

6.Schematic ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 22

7.Printed Circuit Board ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 34

8.Mechanical Exploded Diagram ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 35

9.Part List ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 38

-2-

-3-

1. Safety Precautions

(1) When moving or laying down a LCD Set, please deal with care. Avoid any impact towards

the LCD Set.

(2) Do not leave a broken LCD Set on for a long time. To prevent any further damages, after

check the broken Set’s condition, make sure to turn the power (AC) off.

(3) When opening the BACK COVER, you must turn off power (AC) to prevent any electric

shock.

(4) When loosening screws, check the connecting position and type of the screw.

Sort out the screws and store them separately
Because screws holding PCBs are working as electric circuit grounding,
make sure to check if any screw is missing when assembling.

(5) A LCD Set contains different kinds of connector cables.

When connecting or disconnecting connector cables, check the direction and position
of the cable beforehand.

(6) When disconnecting connectors unplug the connectors slowly with care.

(7) Connectors are designed so that if the number of pins or the direction does not match,

connectors will not fit.
When having problem in plugging the connectors, make sure to check their kind, position,
and direction.

-4-

2. Product Specification

Features

LCD Panel

TV System

Input

Connector

Output

Connector

Sound

Output

Power

Consumption

Dimension

(W x H x D)

Screen Size
Aspect Ratio

Resolution
Pixel Pitch

RF

Contrast

Ratio

Receiving

System

46” 42”

16 : 9

1800 : 1

DVB-T,
PAL, SECAM,
NTSC(AV)

DVB-T,
PAL, SECAM,
NTSC(AV)

DVB-T,
PAL, SECAM,
NTSC(AV)

DVB-T,
PAL, SECAM,
NTSC(AV)

75 Ohm Coaxial

S-Video

1

SCART

2

75 Ohm Coaxial

1

2

Component

RCA X 1

PC RGB

D-Sub X 1

PC Audio

3.5mm Mini-Jack

SPDIF

Optical-Jack Optical-Jack Optical-Jack Optical-Jack

10W

260W 230W

1114 x 745.5 x

125.5(mm)

1044 x 692 x
125(mm)

1114 x 745.5 x

125.5(mm)

1044 x 692 x

124.9(mm)

Max
Power

Source

Set

Dimension

220 ~ 240V,

50~60Hz

220 ~ 240V,

50~60Hz

220 ~ 240V,

50~60Hz

220 ~ 240V,

50~60Hz

HDMI

RCA X 1
D-Sub X 1

75 Ohm Coaxial 75 Ohm Coaxial

11

22

RCA X 1 RCA X 1
D-Sub X 1 D-Sub X 1

3.5mm Mini-Jack

10W

260W 210W

3.5mm Mini-Jack 3.5mm Mini-Jack

Headphone
RF-out

3.5mm Mini-Jack

1111

3.5mm Mini-Jack 3.5mm Mini-Jack 3.5mm Mini-Jack

10W 10W

1920 x 1080 1920 x 1080

0.17675mm x

0.17675mm
1000 : 1 1800 : 1 1000 : 1

1366 x 768 1366 x 768

0.4845mm x

0.4845mm

0.7455mm x

0.7455mm

0.227mm x

0.681mm x RGB

16 : 9 16 : 9 16 : 9

46” 42”

DLT-46U1UMB

DLT-42U1GMB

2222

DLT-42G1LTBDDLT-46U1STB

2-1.PRODUCT SPECIFCATION

-5-

Product Specification

2-2.Available Input Signal

2-2-1.DLT-46U1UMB, DLT-42U1GMB

Resolution

640 x 480

800 x 600

1024 x 768

1280 x 1024

480P
576P

720P

1080i

480i
576i

1920 x 1080i

V-freg

60Hz

HDMI

O

O

X
75Hz
60Hz
75Hz
60Hz
75Hz

60Hz

60Hz

75Hz

50Hz
50Hz

60Hz
50Hz

60Hz
50Hz

60Hz
60Hz
60Hz

O

O

X

O

O

X

O

O

X

O

O

X

O

O

X

O

O

X

O

O

X

O

O
O

O
O

X

O

O

O

O

O

O

O

O

O
X

X

O

X

O

X

O

O

O

O

O

X

O
O
X

PC(D-Sub) Component Standard

VESA Standard
VESA Standard

VESA Standard
VESA Standard
VESA Standard
VESA Standard

-6-

Product Specification

2-2-2.DLT-46U1STB, DLT-42G1LTBD

Resolution

640 x 480

800 x 600

1024 x 768

1360 x 768

480P
576P

720P

1080i

480i
576i

V-freg

60Hz

HDMI

O

O

X

72Hz

60Hz
72Hz

60Hz
70Hz

60Hz
60Hz

50Hz
50Hz

60Hz
50Hz

60Hz
60Hz

50Hz

O

O

X

O

O

X

O

O

X

75Hz

O

O

X

O

O

X

O

O

X

O

O

X

O

O
O

O

O

X
X

O

O
X

X

O

X

O

X

O

O

O

O

X
X

O

X
X

PC(D-Sub) Component Standard

75Hz

O

O

X

VESA Standard
VESA Standard

VESA Standard

VESA Standard
VESA Standard

75Hz

O

O

X

VESA Standard

-7-

Product Specification

2-2-3.Available PIP Mode

Main/Sub

TV

AV 1

XXX X X OO

AV 1

XXX X X OO

AV 2

XXX X X OO

XXX X X OO

DVB

XXX X X OO

HDMI 1

OOO O O X X

HDMI 1

OOO O O X X

AV 2

AV 3/
S-Video

AV 3/
S-Video

DVB HDMI 1 HDMI 2

TV

-8-

3. Block Diagram

3-1.Signal Block Diagram

-9-

Block Diagram

3-2.Power Tree

-10-

4. SERVICE MODE

Using the Service Remote controller, you can enter service mode directly.
SERVICE REMOCON : R-34SVC(S/N:48B3034SVC)

4-1.EEPROM initial DATA

Key

S1
S2

S3

S4

Name

Heat Run Mode

Volume Test

EDID write

S5

PANEL TEST

S6

S7

S8

PICTURE TEST

Default

0
0

0
300
290
290

Don’t use
Don’t use

CUT OFF R
CUT OFF G
CUT OFF B
DRIVE R
DRIVE G
DRIVE B
Auto Y Clamp
Auto Y Gain

Adjustment
fix
fix
fix
fix
fix
fix
fix
fix

White balance &
EEPROM Erase

Gumi channel map write
Volume 0->32->63->L->R

1.Connect jumper(I2C)

2.Press "S4" key and then, TV set display "EDID WRITE
OK" upper left of screen.

3.If EDID writing is fail, TV set display "EDID Write Error"
upper left of screen.

4.After EDID write, remove jumper

1.Press the "S8" key.

2.Press the "OK" key of user remocon. And then TV set
display " EEPROM CLEARED" upper left of screen.

3.When you turn off/on AC POWER. EEPROM data will
be cleared.

PATTERN: BLACK -> WHITE -> RED -> GREEN -> BLUE

DEMPOL CHANNEL MAP WRITE

PATTERN: BRIGHT MIN -> CEN-> MAX ->

CONTRAST MIN -> CEN -> MAX->
COLOR MIN -> CEN -> MAX

Operating Method

EEPROM Erase
operating method

Details

Default

Function

Adjustment

-11-

SERVICE MODE

S9

Device control 1

S10

40
128
121
121

0
3
off

on
186
126
16
0
0
0
23
178
178
128
0
+2
1
1

SSC ON -> OFF

0

42 INCH : 255
46 INCH :

42 inch : 42
46 inch : 46

42 inch : 32
46 inch : 20

148

C2

Video sub bri
Video sub Cb
Video sub Cr
Video sub hue
Video sub cont
Video YC delay
Pedestal level
Anti alias
PIP Brightness
PIP Contrast
Y/G Clamp
Pb Clamp
Pr Clamp
Y/G Gain
Peaking Threthold
Peaking Pos-Gain
Peaking Neg-Gain
APL
Threshold
Tuner AGC
Cb Offset
Cr Offset
SSC Enable
SSC DATA

Dimming Control

Panel Type

Key Type

Normal Brightness

Normal Control

fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
fix
Off
fix

fix

fix

0~255

-12-

S10

S11
S12

Main : Analog upgrade
DVB-T : DVB-T upgrade

Software Upgrade

For debugging mode

I2C Stop
Shipping

fix

SERVICE MODE

4-2. Description of SERVICE MODE ITEM

A. S1(1): Heat-Run Key
B. S2(2): Gumi Channel Map Write
C. S3(3): Volume Test

=> This key can check sound

D. S4(4): EDIE WRITE

=> Using this key, you can update EDID data below method.

1. Connect two jumpers (P502) vertically

2. Press "S4" key and then, TV set display "EDID WRITE OK" upper left of screen.

3. If EDID writing is fail, TV set display "EDID Write Error" upper left of screen.

4. After EDID write, remove jumper

E. S5(5): PANEL TEST

=> Using this key, you can test problem of PANEL, as confirm white pattern, red

pattern,blue pattern, green pattern

F. S6(6): PICTURE TEST

=> Using this key, you can test brightness, contrast and color.
G. S7(7): DEMPOL CHANNEL MAP WRITE
H. S8(8): EEPROM Erase and White Balance adjustment

=> Using this key, you can erase EEPROM data and adjust White balance.
I. S9(9): Device control

=> This key only use for R&D.
J. S10(10): Option key

=> Using this key, you can adjust SSC, Dimming, Panel Type, Control key and etc.
K. S11(11): I2C STOP key

=> This key only use for R&D.
L. S12(SLEEP): Shipping key

=> Using this key, you can set up at shipping mode.

-13-

5. Trouble Shooting

5-1. No signal : OSD is working but on images are displaying

-14-

A. When “No signal” in RF, SCART1,SCART2,AV3

1) First check if other inputs are working
=>If other inputs are not working, replace MAIN PCB

2) Checking waveforms with Color Bar Pattern (Using the oscilloscope)

-Main TP (RF): CC613 near IC601 (Top)

-Main TP(SCART1): LC019 near JP208 (Top)

-Main TP(SCART2): LC213 near JP207 (Top)

-Main TP(AV3): RC055 near P240
=> If all TP signal does not appear, replace MAIN PCB.

B. When “No Signal” in Y/C signal (S-Video)

1) First check if other inputs are working
=>If other inputs are not working, replace MAIN PCB

2) Checking waveforms with Color Bar Pattern (Using the oscilloscope)

-Main TP(Y signal): RC053 near P240

-Main TP(C signal): RC050 near P240
=> If all TP signal does not appear, replace MAIN PCB.

CVBS signal (CC613, LC019, LC213, RC055)

Y signal (RC053)

Trouble Shooting

-15-

Trouble Shooting

C signal (RC050)

Y signal (RC233)

C. When “No Signal” in Y/Pb/Pr signal (Component)

1) First check if other inputs are working
=>If other inputs are not working, replace MAIN PCB

2) Checking waveforms with Color Bar Pattern (Using the oscilloscope)

-Main TP (COMP_Y): RC233 near JP211 (Top)

-Main TP (COMP_Pb): RC234 near JP211 (Top)

-Main TP (COMP1_Pr): RC235 near JP211 (Top)
=> If all TP signal does not appear, replace MAIN PCB.

-16-

Trouble Shooting

D. When “No Signal” in PC

1) First check if other inputs are working
=>If other inputs are not working, replace MAIN PCB

2) Checking waveforms with Color Bar Pattern (Using the oscilloscope)

-Main TP(R signal): RC629 near IC601(Top)

-Main TP(G signal): RC627 near IC601 (Top)

-Main TP(B signal): RC628 near IC601 (Top)

-Main TP(H-Sync): RC630 near IC601 (Top),

-Main TP(V-Sync): RC640 near IC601 (Top)
=> If all TP signal does not appear, replace MAIN PCB.

Pb signal (RC234)

Pr Signal (RC235)

-17-

Trouble Shooting

1024 X 768, 60Hz

R signal (RC629 near IC601)

G Signal (RC627 near IC601)