LG 42LF66-ZE User manual

LCD TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : LD75A
MODEL : 42LF66 42LF66-ZE
website:http://biz.LGservice.com

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CONTENTS
CONTENTS .............................................................................................. 2
SAFETY PRECAUTIONS ..........................................................................3
SPECIFICATION ........................................................................................6
ADJUSTMENT INSTRUCTION ...............................................................15
TROUBLE SHOOTING ............................................................................19
BLOCK DIAGRAM...................................................................................27
EXPLODED VIEW .................................................................................. 29
EXPLODED VIEW PARTS LIST..............................................................30
REPLACEMENT PARTS LIST ............................................................... 31
SVC. SHEET ...............................................................................................

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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
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.
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 1MΩand 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
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

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CAUTION: Before servicing receivers covered by this service
manual and its supplements and addenda, read and follow the
SAFETY PRECAUTIONS on page 3 of this publication.
NOTE: If unforeseen circumstances create conflict between the
following servicing precautions and any of the safety precautions on
page 3 of this publication, always follow the safety precautions.
Remember: Safety First.
General Servicing Precautions
1. Always unplug the receiver AC power cord from the AC power
source before;
a. Removing or reinstalling any component, circuit board
module or any other receiver assembly.
b. Disconnecting or reconnecting any receiver electrical plug or
other electrical connection.
c. Connecting a test substitute in parallel with an electrolytic
capacitor in the receiver.
CAUTION: A wrong part substitution or incorrect polarity
installation of electrolytic capacitors may result in an
explosion hazard.
2. Test high voltage only by measuring it with an appropriate high
voltage meter or other voltage measuring device (DVM,
FETVOM, etc) equipped with a suitable high voltage probe.
Do not test high voltage by "drawing an arc".
3. Do not spray chemicals on or near this receiver or any of its
assemblies.
4. Unless specified otherwise in this service manual, clean
electrical contacts only by applying the following mixture to the
contacts with a pipe cleaner, cotton-tipped stick or comparable
non-abrasive applicator; 10% (by volume) Acetone and 90% (by
volume) isopropyl alcohol (90%-99% strength)
CAUTION: This is a flammable mixture.
Unless specified otherwise in this service manual, lubrication of
contacts in not required.
5. Do not defeat any plug/socket B+ voltage interlocks with which
receivers covered by this service manual might be equipped.
6. Do not apply AC power to this instrument and/or any of its
electrical assemblies unless all solid-state device heat sinks are
correctly installed.
7. Always connect the test receiver ground lead to the receiver
chassis ground before connecting the test receiver positive
lead.
Always remove the test receiver ground lead last.
8. Use with this receiver only the test fixtures specified in this
service manual.
CAUTION: Do not connect the test fixture ground strap to any
heat sink in this receiver.
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid-state) devices can be damaged easily
by static electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of typical ES
devices are integrated circuits and some field-effect transistors and
semiconductor "chip" components. The following techniques
should be used to help reduce the incidence of component
damage caused by static by static electricity.
1. Immediately before handling any semiconductor component or
semiconductor-equipped assembly, drain off any electrostatic
charge on your body by touching a known earth ground.
Alternatively, obtain and wear a commercially available
discharging wrist strap device, which should be removed to
prevent potential shock reasons prior to applying power to the
unit under test.
2. After removing an electrical assembly equipped with ES
devices, place the assembly on a conductive surface such as
aluminum foil, to prevent electrostatic charge buildup or
exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES
devices.
4. Use only an anti-static type solder removal device. Some solder
removal devices not classified as "anti-static" can generate
electrical charges sufficient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate
electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective
package until immediately before you are ready to install it.
(Most replacement ES devices are packaged with leads
electrically shorted together by conductive foam, aluminum foil
or comparable conductive material).
7. Immediately before removing the protective material from the
leads of a replacement ES device, touch the protective material
to the chassis or circuit assembly into which the device will be
installed.
CAUTION: Be sure no power is applied to the chassis or circuit,
and observe all other safety precautions.
8. Minimize bodily motions when handling unpackaged
replacement ES devices. (Otherwise harmless motion such as
the brushing together of your clothes fabric or the lifting of your
foot from a carpeted floor can generate static electricity
sufficient to damage an ES device.)
General Soldering Guidelines
1. Use a grounded-tip, low-wattage soldering iron and appropriate
tip size and shape that will maintain tip temperature within the
range or 500°F to 600°F.
2. Use an appropriate gauge of RMA resin-core solder composed
of 60 parts tin/40 parts lead.
3. Keep the soldering iron tip clean and well tinned.
4. Thoroughly clean the surfaces to be soldered. Use a mall wire-
bristle (0.5 inch, or 1.25cm) brush with a metal handle.
Do not use freon-propelled spray-on cleaners.
5. Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.
(500°F to 600°F)
b. Heat the component lead until the solder melts.
c. Quickly draw the melted solder with an anti-static, suction-
type solder removal device or with solder braid.
CAUTION: Work quickly to avoid overheating the circuit
board printed foil.
6. Use the following soldering technique.
a. Allow the soldering iron tip to reach a normal temperature
(500°F to 600°F)
b. First, hold the soldering iron tip and solder the strand against
the component lead until the solder melts.
c. Quickly move the soldering iron tip to the junction of the
component lead and the printed circuit foil, and hold it there
only until the solder flows onto and around both the
component lead and the foil.
CAUTION: Work quickly to avoid overheating the circuit
board printed foil.
d. Closely inspect the solder area and remove any excess or
splashed solder with a small wire-bristle brush.
SERVICING PRECAUTIONS

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IC Remove/Replacement
Some chassis circuit boards have slotted holes (oblong) through
which the IC leads are inserted and then bent flat against the
circuit foil. When holes are the slotted type, the following technique
should be used to remove and replace the IC. When working with
boards using the familiar round hole, use the standard technique
as outlined in paragraphs 5 and 6 above.
Removal
1. Desolder and straighten each IC lead in one operation by gently
prying up on the lead with the soldering iron tip as the solder
melts.
2. Draw away the melted solder with an anti-static suction-type
solder removal device (or with solder braid) before removing the
IC.
Replacement
1. Carefully insert the replacement IC in the circuit board.
2. Carefully bend each IC lead against the circuit foil pad and
solder it.
3. Clean the soldered areas with a small wire-bristle brush.
(It is not necessary to reapply acrylic coating to the areas).
"Small-Signal" Discrete Transistor
Removal/Replacement
1. Remove the defective transistor by clipping its leads as close as
possible to the component body.
2. Bend into a "U" shape the end of each of three leads remaining
on the circuit board.
3. Bend into a "U" shape the replacement transistor leads.
4. Connect the replacement transistor leads to the corresponding
leads extending from the circuit board and crimp the "U" with
long nose pliers to insure metal to metal contact then solder
each connection.
Power Output, Transistor Device
Removal/Replacement
1. Heat and remove all solder from around the transistor leads.
2. Remove the heat sink mounting screw (if so equipped).
3. Carefully remove the transistor from the heat sink of the circuit
board.
4. Insert new transistor in the circuit board.
5. Solder each transistor lead, and clip off excess lead.
6. Replace heat sink.
Diode Removal/Replacement
1. Remove defective diode by clipping its leads as close as
possible to diode body.
2. Bend the two remaining leads perpendicular y to the circuit
board.
3. Observing diode polarity, wrap each lead of the new diode
around the corresponding lead on the circuit board.
4. Securely crimp each connection and solder it.
5. Inspect (on the circuit board copper side) the solder joints of
the two "original" leads. If they are not shiny, reheat them and if
necessary, apply additional solder.
Fuse and Conventional Resistor
Removal/Replacement
1. Clip each fuse or resistor lead at top of the circuit board hollow
stake.
2. Securely crimp the leads of replacement component around
notch at stake top.
3. Solder the connections.
CAUTION: Maintain original spacing between the replaced
component and adjacent components and the circuit board to
prevent excessive component temperatures.
Circuit Board Foil Repair
Excessive heat applied to the copper foil of any printed circuit
board will weaken the adhesive that bonds the foil to the circuit
board causing the foil to separate from or "lift-off" the board. The
following guidelines and procedures should be followed whenever
this condition is encountered.
At IC Connections
To repair a defective copper pattern at IC connections use the
following procedure to install a jumper wire on the copper pattern
side of the circuit board. (Use this technique only on IC
connections).
1. Carefully remove the damaged copper pattern with a sharp
knife. (Remove only as much copper as absolutely necessary).
2. carefully scratch away the solder resist and acrylic coating (if
used) from the end of the remaining copper pattern.
3. Bend a small "U" in one end of a small gauge jumper wire and
carefully crimp it around the IC pin. Solder the IC connection.
4. Route the jumper wire along the path of the out-away copper
pattern and let it overlap the previously scraped end of the good
copper pattern. Solder the overlapped area and clip off any
excess jumper wire.
At Other Connections
Use the following technique to repair the defective copper pattern
at connections other than IC Pins. This technique involves the
installation of a jumper wire on the component side of the circuit
board.
1. Remove the defective copper pattern with a sharp knife.
Remove at least 1/4 inch of copper, to ensure that a hazardous
condition will not exist if the jumper wire opens.
2. Trace along the copper pattern from both sides of the pattern
break and locate the nearest component that is directly
connected to the affected copper pattern.
3. Connect insulated 20-gauge jumper wire from the lead of the
nearest component on one side of the pattern break to the lead
of the nearest component on the other side.
Carefully crimp and solder the connections.
CAUTION: Be sure the insulated jumper wire is dressed so the
it does not touch components or sharp edges.

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1. Application range
This spec sheet is applied to the 37", 42", 47" LCD TV used
LD75A chassis.
2. Specification
Each part is tested as below without special appointment.
(1) Temperature : 25 ± 5°C(77 ± 9°F), CST : 40 ± 5°C
(2) Relative Humidity : 65% ± 10%
(3) Power Voltage : Standard input voltage (100-240V~,
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.
3. Test method
(1) Performance : LGE TV test method followed
(2) Demanded other specification
Safety : CE, IEC Specification
EMC : CE, IEC
SPECIFICATION
NOTE : Specifications and others are subject to change without notice for improvement .
4. General Specification(FHD Module)
Item Specification Measurement Result Remark
Display Screen Device 47/42/37 inch Wide Color Display Module LCD
Aspect Ratio 16:9
LCD Module 37LB5DF (37LF65): LC370WU1-SL01
42LB5DF (42LF65): LC420WU2-SLB1
47LB5DF (47LF65): LC470WU1-SLB2
37LF66: LC370WU1-SL01
42LF66: LC420WU2-SLB1
47LF66: LC470WU1-SLB2
Operating Environment 1) Temp. : 0 ~ 40 deg
2) Humidity : 10 ~ 90% LGE SPEC
Storage Environment 3) Temp. : -20 ~ 50 deg
4) Humidity : 10 ~ 90 %
Input Voltage AC100 ~ 240V, 50/60Hz Maker LG

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5. Chroma & Brightness
5-1. FHD Module-47LF66
Item Min Typ Max Unit Measurement Result Remark
Viewing Angle R/L 178 Viewing R/L 178
<CR>10> U/D 178 Angle<CR>10> U/D 178
White average 47LF65 450 550 - cd/m2- 100IRE Full White Pattern(255gray)
brightness - Picture : Dynamic (Cool)
Brightness uniformity 1.3 0 1.3 cd/m2- 100IRE Full White Pattern(255gray)
- Picture : Dynamic (Cool)
Color White X 0.261 0.276 0.291 - 85IRE Full White Pattern (216 gray)
Coordinate Y0.268 0.283 0.298 - Picture : Dynamic (Cool)
Red X 0.603 0.618 0.633
Y0.318 0.333 0.348
Green X 0.260 0.275 0.290
Y0.568 0.583 0.598
Blue X 0.132 0.147 0.162
Y0.046 0.061 0.076
Color coordinate uniformity -0.03 Average +0.03 - 85IRE Full White Pattern (216 gray)
- Picture : Dynamic (Cool)
Contrast Ratio CR with - Full white(100IRE)
at dark room PWM-Dimming 4000 : 1 5000 : 1 - Full black(0IRE) pattern
CR without (600:1) (800:1) - Picture : Dynamic (Cool)
PWM-Dimming -Input:TV/DTV/AV1,2,3/Comp/HDMI1,2
-> CR with PWM-Dimming
RGB/HDMI-PC
-> CR without PWM-Dimming
Color Medium 8300 9300 10300 - 85IRE Full White Pattern (216 gray)
Temperature Warm 5500 6500 7500 - Picture : Dynamic (Cool)
Cool 10000 11000 12000
Color pull in PAL -500 +500 Hz
Range NTSC -500 +500 Hz
Color killer Sensitivity -80 dBm
*** PWM-Dimming function works after 30 seconds. So, When you check the CR, you must wait 30 minutes for check the Full Black
level and then 10 minutes for check the Full White level.***

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5-2. FHD Module-42LF66
Item Min Typ Max Unit Measurement Result Remark
Viewing Angle R/L 178 Viewing Angle R/L 178
<CR>10> U/D 178 <CR>10> U/D 178
White average 42LF65 450 550 - cd/m2- 100IRE Full White Pattern (255gray)
brightness - Picture : Dynamic (Cool)
Brightness uniformity 1.3 0 1.3 cd/m2- 100IRE Full White Pattern (255gray)
- Picture : Dynamic (Cool)
Color White X 0.261 0.276 0.291 - 85IRE Full White Pattern (216 gray)
Coordinate Y 0.268 0.283 0.298 - Picture : Dynamic (Cool)
Red X 0.603 0.618 0.633
Y0.318 0.333 0.348
Green X 0.260 0.275 0.290
Y0.568 0.583 0.598
Blue X 0.132 0.147 0.162
Y0.046 0.061 0.076
Color coordinate uniformity -0.03 Average +0.03 - 85IRE Full White Pattern (216 gray)
- Picture : Dynamic (Cool)
Contrast Ratio CR with - Full white(100IRE)
at dark room PWM-Dimming 4000 : 1 5000 : 1 - Full black(0IRE) pattern
CR without (400:1) (600:1) - Picture : Dynamic (Cool)
PWM-Dimming
-Input:TV/DTV/AV1,2,3/Comp/HDMI1,2
-> CR with PWM-Dimming
RGB/HDMI-PC
-> CR without PWM-Dimming
Color Medium 8300 9300 10300 - 85IRE Full White Pattern (216 gray)
Temperature Warm 5500 6500 7500 - Picture : Dynamic (Cool)
Cool 10000 11000 12000
Color pull in PAL -500 +500 Hz
Range NTSC -500 +500 Hz
Color killer Sensitivity -80 dBm

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5-3. FHD Module-37LF66
Item Min Typ Max Unit Measurement Result Remark
Viewing Angle R/L 178 Viewing Angle R/L 178
<CR>10> U/D 178 <CR>10> U/D 178
White average 37LF65 400 500 - cd/m2- 100IRE Full White Pattern (255gray)
brightness - Picture : Dynamic (Cool)
Brightness uniformity 1.3 0 1.3 cd/m2- 100IRE Full White Pattern (255gray)
- Picture : Dynamic (Cool)
Color White X 0.261 0.276 0.291 - 85IRE Full White Pattern (216 gray)
Coordinate Y 0.268 0.283 0.298 - Picture : Dynamic (Cool)
Red X 0.603 0.618 0.633
Y0.318 0.333 0.348
Green X 0.260 0.275 0.290
Y0.595 0.610 0.625
Blue X 0.132 0.147 0.162
Y0.046 0.061 0.076
Color coordinate uniformity -0.03 Average +0.03 - 85IRE Full White Pattern (216 gray)
- Picture : Dynamic (Cool)
Contrast Ratio CR with - Full white(100IRE)
at dark room PWM-Dimming 4000 : 1 5000 : 1 - Full black(0IRE) pattern
CR without (400:1) (600:1) - Picture : Dynamic (Cool)
PWM-Dimming
- Input:TV/DTV/AV1,2,3/Comp/HDMI1,2
-> CR with PWM-Dimming
RGB/HDMI-PC
-> CR without PWM-Dimming
Color Medium 8300 9300 10300 - 85IRE Full White Pattern (216 gray)
Temperature Warm 5500 6500 7500 - Picture : Dynamic (Cool)
Cool 10000 11000 12000
Color pull in PAL -500 +500 Hz
Range NTSC -500 +500 Hz
Color killer Sensitivity -80 dBm

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6. Component Video Input (Y, PB, PR)
No Resolution H-freq(kHz) V-freq.(kHz) Pixel clock(MHz) Proposed
1720*480 15.73 59.94 13.500 SDTV, DVD 480I(525I)
2720*480 15.75 60.00 13.514 SDTV, DVD 480I(525I)
3720*576 15.625 50.00 13.500 SDTV, DVD 576I(625I)
4720*480 31.47 59.94 27.000 SDTV 480P
5720*480 31.50 60.00 27.027 SDTV 480P
6720*576 31.25 50.00 27.000 SDTV 576P
71280*720 44.96 59.94 74.176 HDTV 720P
81280*720 45.00 60.00 74.250 HDTV 720P
91280*720 37.50 50.00 74.25 HDTV 720P
10 1920*1080 33.72 59.94 74.176 HDTV 1080I
11 1920*1080 33.75 60.00 74.250 HDTV 1080I
12 1920*1080 28.125 50.00 74.250 HDTV 1080I
13 1920*1080 67.50 60.00 148.50 HDTV 1080P
7. RGB Input (PC)
No Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Proposed Remarks
1. 720*400 31.468 70.08 28.32
2. 640*480 31.469 59.94 25.17 VESA 848*480 60Hz, 852*480 60Hz
37.500 75.00 31.50 ->No signal
640*480 60Hz Display
3800*600 37.879 60.31 40.00 VESA
46.875 75.00 49.50
4. 832*624 49.725 74.55 57.283 Macintosh
51024*768 48.363 60.00 65.00
56.476 70.00 75.00 VESA(XGA)
60.023 75.03 78.75
61280*768 47.693 59.99 80.125 WXGA
71360*768 47.649 59.94 84.625 WXGA
81366*768 47.649 59.94 84.625 WXGA
91280*1024 63.595 60.0 108.875 SXGA
10 1400*1050 65.160 60.0 122.50 SXGA
11 1920*1080 66.647 59.988 138.625 WUXGA Reduced Blanking Timing

- 11 -
0123456789ABCDEF
00FFFF FF FF FF FF 0 1E 6D 72 75 1 1 1 1
10 9 10 1 3 1 46 27 78 EA D9 B0 A3 57 49 9C 25
20 11 49 4B A5 6E 0 31 40 45 40 61 40 81 80 90 40
30 D1 C0 1 1 1 1 1A 36 80 A0 70 38 1F 40 30 20
40 35 0 E8 26 32 0 0 1A DA 2F 78 E0 51 1A 25 40
50 58 98 14 0 E8 26 32 0 0 1A 0 0 0 FD 0 39
60 4B 1F 54 12 0 0A 20 20 20 20 20 20 0 0 0 FC
70 0 33 37 4C 46 36 35 2D5A432020 2020 0 FF
<Example : 37LF65-ZC RGB EDID data>
6CH – 7DH : Model name
7EH : No Extension EDID Block
7FH : Check sum
Model Name : 47LF66 / Check Sum : FE
Model Name : 42LF65 / Check Sum : 03
Model Name : 37LF65 / Check Sum : FF
7-1. EDID Input (PC)
8. HDMI Input (DTV)
No Resolution H-freq(kHz) V-freq.(kHz) Pixel clock(MHz) Proposed Remarks
1. 720*480 31.47 59.94 27.00 SDTV 480P(4:3)
2. 720*480 31.50 60 27.027 SDTV 480P(4:3) If change PC
3. 640*480 31.469 59.94 25.175 SDTV 480P(4:3) 640*480 60Hz Display
4. 640*480 31.469 60.00 25.20 SDTV 480P(4:3)
5. 720*480 31.47 59.94 27.000 SDTV 480P(16:9)
6. 720*480 31.50 60.00 27.027 SDTV 480P(16:9)
7. 720*576 31.25 50.00 27.000 SDTV 576P
8. 1280*720 37.50 50.00 74.176 HDTV 720P
9. 1280*720 44.96 59.94 74.176 HDTV 720P If change PC
10. 1280*720 45.00 60.00 74.250 HDTV 720P 1280*720 60Hz Display
11 1920*1080 33.72 59.94 74.176 HDTV 1080I
12 1920*1080 33.75 60.00 74.250 HDTV 1080I
13 1920*1080 28.125 50.00 74.250 HDTV 1080I 50Hz
14 1920*1080 27.000 24.00 74.250 HDTV 1080P 24Hz
15 1920*1080 56.250 50 148.500 HDTV 1080P 50Hz
16 1920*1080 67.433 59.94 148.352 HDTV 1080P If change PC
17 1920*1080 67.500 60 148.500 HDTV 1080P 1920*1080 60Hz∑Œ Display

- 12 -
8. HDMI Input (PC)
No Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Proposed Remarks
1. 720*400 31.468 70.08 28.32
If change DTV
2. 640*480 31.469 59.94 25.17 VESA 480p Display
37.500 75.00 31.50 848*480 60Hz, 852*480 60Hz
: No signal
3800*600 37.879 60.31 40.00 VESA
46.875 75.00 49.50
4. 832*624 49.725 74.55 57.283 Macintosh
48.363 60.00 65.00
51024*768 56.476 70.00 75.00 VESA(XGA)
60.023 75.03 78.75
61280*768 47.693 59.99 80.125 WXGA
71360*768 47.649 59.94 84.625 WXGA
81366*768 47.649 59.94 84.625 WXGA
91280*1024 63.595 60.0 108.875 SXGA
10 1400*1050 65.160 60.0 122.50 SXGA Reduced Blanking Timing
11 1600*1200 74.077 60.0 130.375 UXGA 1920*1200 60Hz
No Signal
Reduced Blanking Timing
12 1920*1080 66.647 59.988 138.625 WUXGA If change DTV
1080p Display
0123456789ABCDEF
00FFFF FF FF FF FF 0 1E 6D 72 75 1 1 1 1
10 9 10 1 3 80 46 27 78 EA D9 B0 A3 57 49 9C 25
20 11 49 4B A5 6E 0 31 40 45 40 61 40 81 80 90 40
30 A9 40 D1 C0 1 1 1A 36 80 A0 70 38 1F 40 30 20
40 35 0 E8 26 32 0 0 1A 1B 21 50 A0 51 0 1E 30
50 48 88 35 0 BC 86 21 0 0 1C 0 0 0 FD 0 39
60 4B 1F 54 12 0 0A 20 20 20 20 20 20 0 0 0 FC
70 0 33 37 4C 46 36 35 2D5A432020 2020 1 D8
80 2 3 21 F1 4E 81 2 3 15 12 13 4 14 5 20 21
90 22 1F 10 23 9 7 7 83 1 0 0 65 3 0C 0 10
A0 0 1 1D 0 80 51 D0 1C 20 40 80 35 0 BC 88 21
B0 0 0 1E 8C 0A D0 8A 20 E0 2D 10 10 3E 96 0 13
C0 8E 21 0 0 18 2 3A 80 18 71 38 2D 40 58 2C 45
D0 0 6 44 21 0 0 1E 1 1D 80 18 71 1C 16 20 58
E0 2C 25 0 C4 8E 21 0 0 9E 4E 1F 0 80 51 0 1E
F0 30 40 80 37 0 BC 88 21 0 0 18 0 0 0 0 1D
<Example : 37LF65-ZC HDMI1 EDID data>
6CH – 7DH : Model name
7EH : Extension EDID Block
7FH : Check sum
9FH : Vendor specification Block (10 : HDMI1, 20 : HDMI2)
FFH : Check sum valid
Model Name : 47LF66 / Check Sum HDMI1 : D71D , HDMI2 : D70D
Model Name : 42LF66 / Check Sum HDMI1 : DC1D , HDMI2 : DC0D
Model Name : 37LF66 / Check Sum HDMI1 : D81D , HDMI2 : D80D
8-1. EDID Input (HDMI)

- 13 -
9. MODULE
9-1. General specifications-47LF66: LC470WU1-SLB2
No Item Min Typ Max Unit Remark
1Display area 1039.68 (H) * 584.82(V) mm
2Outline dimension 1096 (W) x 640 (H) x 48.1 (D) mm
with inverter
3Number of Pixels 1920 (H) x 1080(V) 1Pixel=3RGB Cells
4Cell pitch 541.5um (H) x 541.5um (V) um G cell
5Color arrangement RGB stripe arrangement
6Weight(net) 20 Kg Net 1EA
9-2. General specifications-42LF66: LC420WU2-SLB1
No Item Min Typ Max Unit Remark
1Display area 930.24 (H) * 523.26 (V) mm
2Outline dimension 983 (W) x 576 (H) x 51 (D) mm
with inverter
3Number of Pixels 1920 (H) x 1080(V) 1Pixel=3RGB Cells
4Cell pitch 484.5um (H) x 484.5um (V) um G cell
5Color arrangement RGB stripe arrangement
6Weight(net) 13 Kg Net 1EA
9-3. General specifications-37LF66: LC370WU1-SL01
No Item Min Typ Max Unit Remark
1Display area 819.36 (H) * 460.89 (V) mm
2Outline dimension 877 (W) x 516.8 (H) x 55.5 (D) mm
with inverter
3Number of Pixels 1920 (H) x 1080(V) 1Pixel=3RGB Cells
4Cell pitch 426.75um (H) x 426.75um (V) um G cell
5Color arrangement RGB stripe arrangement
6Weight(net) 10.5 Kg Net 1EA

- 14 -
10. Mechanical specification
10-1. 47LF66
No Item Content Remark
1Product Width (W) Length (D) Height (H)
Dimension Before Packing 1144.5 331 825.6 With Stand
After Packing 1230 410 912
2Product Only SET 37.46 kg With Stand
Weight With BOX 44.7 kg
10-2. 42LF66
No Item Content Remark
1Product Width (W) Length (D) Height (H)
Dimension Before Packing 1033.1 300 750 With Stand
After Packing 1119 374 858 With Stand
2Product Only SET 27.5Kg With Stand
Weight With BOX 32.5Kg
10-3. 37LF66
No Item Content Remark
1Product Width (W) Length (D) Height (H)
Dimension Before Packing 1113.3 294.3 722.5 With Stand
After Packing 1191 378 835 With Stand
2Product Only SET 30.1Kg With Stand
Weight With BOX 34.6Kg

- 15 -
ADJUSTMENT INSTRUCTION
1. Application Range
This spec. sheet is applied to all of the LD75A chassis
manufactured at LG TV Plant all over the world.
Ex.) LD75A : 37/42/47LB5DF-ZC, 37/42/47LY3DF-ZA
2. Specification
1.1 Because this is not a hot chassis, it is not necessary to
use an isolation transformer.
However, the use of isolation transformer will help to
protect test instruments.
1.2 Adjustment must be done in the correct sequence.
1.3 The adjustment must be performed at 25°æ5∞C
temperature and 65°æ10% relative humidity if there is
no specified designation.
1.4 The input voltage of the receiver must be kept between
100~220V, 50/60Hz.
1.5 Before adjustment, execute Heat-Run for 30 minutes at
RF no signal.
3. Channel Recover
* Use Channel Recover of System Control3 of Service
Menu. You can load The Channel Map In LGEMA and
LGEWR
1) Press ADJ key on Service Remote Control. And then
Choice System Control3.
2) Choice Channel Recover.
3) Press " " key. You can See "OK" letter. And Then The
Set power off automatically.
3) After Turn on the SET. You can confirm The Channel
map on Programme Edit OSD.
Warning … If you press IN-STOP key, The channel map
will disappear.
4. EDID
* When do Set Assembly, EDID data must scan in DDC
line.
Caution
* Use the proper signal cable for EDID Download
- Analog EDID : Pin3 exists
- Digital EDID : Pin3 exists
* Caution: - Never connect HDMI & D-sub Cable
at the same time.
- Use the proper cables below for
EDID Writing.
4.1. EDID Data
4.2. Data (Refer to Product specification)
1> ANALOG (128Bytes)
2> HDMI (256Bytes)
* Detail EDID Options are below ( , , , , )
Product ID
Month, Year : Controlled on production line:
ex) Monthly : ‘09’ -> ‘09’
Year : ‘2006’ -> ‘10’
Model Name(Hex) :
Checksum : Changeable by total EDID data.
* Before AV ADC Calibration, should be executed the Tool
Option setting.
Item Condition Hex(16) Data
Manufacturer ID GSM 1E6D
Version Digital : 1 01
Revision Digital : 3 03
Model Name Product ID Product ID
DEC Hex EDID Table
37/42/47LF65 XXXX XX XX XXXX
37/42/47LY95 XXXX XX XX XXXX
Model Name Model Name(Hex)
37/42/47LF65 XXXX
37/42/47LY95 XXXX
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
00 00 FF FF FF FF FF FF 00 1E 6D
01 01 03 01 46 27 78 EA D9 B0 A3 57 49 9C 25
02 11 49 4B A5 6E 80 31 40 45 40 61 40 D1 C0 01 01
03 01 01 01 01 01 01 1B 21 50 A0 51 00 1E 30 48 88
04 35 00 BC 88 21 00 00 1C 4E 1F 00 80 51 00 1E 30
05 35 00 BC 88 21 00 00 1C 4E 1F 00 80 51 00 1E 30
06 4B 1F 3D 09 00 0A 20 20 20 20 20 20
07 00
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
00 00 FF FF FF FF FF FF 00 1E 6D
01 01 03 80 46 27 78 EA D9 B0 A3 57 49 9C 25
02 11 49 4B 00 00 00 01 01 01 01 01 01 01 01 01 01
03 01 01 01 01 01 01 8C 0A D0 8A 20 E0 2D 10 10 3E
04 96 00 C4 8E 21 00 00 18 8C 0A D0 90 20 40 31 20
05 0C 40 55 00 C4 8E 21 00 00 18
06 00 00 00 FD
07 00 38 4B 1F 3D 09 00 0A 20 20 20 20 20 20 01
00 02 03 1E F1 4B 82 11 01 03 12 13 04 14 05 1F 10
01 20 21 22 23 09 07 07 83 01 00 00 65 03 0C 00 10
02 00 01 1D 00 BC 52 D0 1E 20 B8 28 55 40 C4 8E 21
03 00 00 1E 01 1D 00 72 51 D0 1E 20 6E 28 55 00 C4
04 8E 21 00 00 1E 01 1D 80 D0 72 1C 16 20 10 2C 25
05 80 C4 8E 21 00 00 9E 01 1D 80 18 71 1C 16 20 58
06 2C 25 00 C4 8E 21 00 00 9E 8C 0A D0 90 20 40 31
07 20 0C 40 55 00 13 8E 21 00 00 18 00 00 00 00 CA

- 16 -
5. Method of Tool Option setting
5.1. Press ADJ Key in the Adjust remocon.
5.2. Select "Tool Option1 and 2" by using (CH+/-) key,
and Press Number Key.
5.3. Model Table.
5.4. After changing, push the EXIT Key.
6. ADC Calibration
* Before adjusting White-balance , the AV ADC should be
done.
* Caution : - System control RS-232 Host should be "PC" for
adjustment.
- Before AV ADC Calibration, execute the "Panel
size selection" (only LCD model)
6.1. Adjustment of AV
- Mandatory point : All models are adjusted PAL in AV
mode
* Required Equipments
Remote controller for adjustment.
MSPG-925FS Pattern Generator (Which has
Video Signal: 7 Color Bar Pattern shown in Fig. 1).
- Model : 202 / Pattern : 65
PAL-BGDHI (composite signal)
6.1.1 Method of Auto AV Color Balance(PAL_BGDHI).
1) Input the Video Signal: 7 Color Bar signal into AV3.
2) Set the PSM to Dynamic mode in the Picture menu.
[Fig.1]
3) Press IN-START key on R/C for adjustment.
4) Press the (Vol.+) key to operate the set, then it
becomes automatically.
5) After downloading complete, the ‘OK’ word
appears.
6) Auto-RGB OK means the adjustment is completed.
6.2. Adjustment of Component
* Required Equipments
Remote controller for adjustment.
MSPG-925FS Pattern Generator. (Which has
720p/50Hz YPbPr output Pattern shown in Fig. 2)
-> Model : 215 / Pattern : 65
6.2.1 Method of Auto Component Color Balance
1) Input the Component 720p/50Hz 7 Color
Bar(MSPG-925FS model:215, pattern:65) signal
into Component.
2) Set the PSM to Dynamic mode in the Picture menu.
[Fig.2]
3) Press the IN-START key on R/C for adjustment.
4) Press the (Vol.+) key to operate the set , then it
becomes automatically.
5) After downloading complete, the ‘OK’ word
appears.
6) Auto-RGB OK means the adjustment is completed.
6.3. Adjustment of RGB
* Required Equipments
Remote controller for adjustment.
MSPG-925FS Pattern Generator
(Which has XGA [1024*768] 60Hz 1/2 black &
white pattern shown in Fig. 3)
6.3.1 Method of Auto RGB Color Balance
1) Input the PC 1024x768 @ 60Hz 1/2 black & white
pattern (MSPG-925FS, Model:3, Pattern:65) into
RGB. (using D-sub to D-sub cable)
2) Set the PSM to Dynamic mode in the Picture menu.
Model name Tool Option1 Tool Option2
37LF65 2320 1701
42LF65 2324 1701
47LF65 2328 1701
37LY95 2384 1701
42LY95 2391 1701
47LY95 2395 1701
ADC AV Component RGB-PC
MSPG925FS PAL Model:215 (720P)
INPUT SELECT AV3 Pattern:65 Model: 3
Model:202(PAL-BGDHI) *720P/50Hz
(1024*768 60Hz)
7 Color Bar Pattern: 65
Pattern: 65
*PAL 7 Color Bar

- 17 -
3) Press the IN-START key on R/C for adjustment.
[Fig.3]
4) Press the (Vol.+) key to operate the set , then it
becomes automatically.
5) After downloading complete, the ‘OK’ word
appears.
6) Auto-RGB OK means adjustment is completed.
7. White Balance
* Test Equipment
Color Analyzer (CA-210, CA-100+ / CH.9)
-> When you adjust LCD color temperature, on Color
analyzer (CA-210, CA-100+), you should use Channel 9
which is Matrix compensated (White, Red, Green, Blue
revised) by CS-1000 and adjust in accordance with
White balance adjustment coordinate which is specified
on the next.
* Color temperature standards according to CSM and Module.
* White balance adjustment coordinate and color temperature.
PC (for communication through RS-232C) -> UART
Baud rate : 115200 bps
* Connecting picture of the measuring instrument (On
Automatic control )
Inside PATTERN is used when W/B is controlled.
Connect to auto controller or push control R/C IN-START
-> Enter the mode of White-Balance, the pattern will come
out.
[Fig.4] connecting picture (On Automatic Control)
* Auto-control interface and directions
1) Adjust in the place where the influx of light like floodlight
around is blocked. (illumination is less than 10ux).
2) In case of PDP: Measure and adjust after sticking the
Color Analyzer (CA-100+, CA210 ) to the side of the
module.
In case of LCD: Adhere closely the Color Analyzer (
CA210 ) to the module less than 10cm distance, keep it
with the surface of the Module and Color Analyzer’s
Prove vertically.(80~100°).
3) Aging time
- After aging start, keep the power on (no suspension of
power supply) and heat-run over 15 minutes.
- In case of PDP, keep white pattern using inside pattern.
- In case of LCD, using ‘no signal’ or ‘full white pattern’ or
the others, check the back light on.
7.1 Auto white Balance
1) setup is done.
2) Test Equipment
Color Analyzer ( CA210, CA-100+)
PC (for communication through RS-232C)
RS-232 Host Ë PC
UART Baud rate Ë 115200
Download Ë Cortez
*** When press Power-on key, this point is automatically
setuped. Pattern Generator (MSPG-925F)
7.2 Manual white Balance
* One of R Gain / G Gain / B Gain should be kept on 80,
and others are controlled lowering from 80
1) Press "power on°" of the control R/C, set heat run to
white by pressing , and heat run over 15 minutes
(Set : RS-233 Host : PC, Baud Rate : 115200bps,
Download: Cortez).
2) Zero Calibrate CA-100+, and when controlling, stick the
sensor to the center of LCD module surface.
3) Double click In-start key on Controlling R/C and get in
‘white balance’.
4) Set test-pattern on and display inside pattern. Control is
carried out on three color temperature, COOL, MEDIUM,
WARM. (Control is carried out three times,)
CSM LCD
Cool 11,000k
Medium 9,300k
Warm 6,500k
Cool CS-1000 CA-210 (CH 9) CA-100+ (CH 9)
X0.276 0.002 0.276 0.002 0.276 0.002
Y0.283 0.002 0.283 0.002 0.283 0.002
Temp 11000 1000 11000
uv 0.000 0.000 0.000
Medium CS-1000 CS-1000 CS-1000
X0.285 0.002 0.285 0.002 0.285 0.002
Y0.293 0.002 0.293 0.002 0.293 0.002
Temp 9300 9300 9300
uv 0.000 0.000 0.000
Warm CS-1000 CS-1000 CS-1000
X0.313 0.002 0.313 0.002 0.313 0.002
Y0.329 0.002 0.329 0.002 0.329 0.002
Temp 6500 6500 6500
Temp 0.003 0.003 0.003

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5) When the R/G/B GAIN is 80 on OSD, it is the FULL
DYNAMIC Range of the Module. In order to control white
balance without the saturation of FULL DYNAMIC Range
and DATA, one of R Gain / G Gain / B Gain should be
kept on 80, and other two is controlled lowering from 80.
* Color Temperature: Cool, Medium, Warm
1. When R GAIN is set to 80
- Control G GAIN and B GAIN by lowering from 80.
2. When B GAIN is set to 80
- Control R GAIN and G GAIN by lowering from 80.
3. When G GAIN is set to 80
- Control R GAIN and B GAIN by lowering from
192.
One of R Gain / G Gain / B Gain should be kept on
80, and adjust other two lower than 80.
(When R/G/B GAIN are all 80, it is the FULL
DYNAMIC Range of Module)
8. Set Information(Serial No & Model
name)
1) Setting up like bottom figure(After setting white balance,
this is set)
(Setting: Press ADJ Key in the Adjust remocon.
Select "System Control 2" by using /(CH+/-) key,
and press (ENTER)
Using Adjust remocon, RS-232 Host & Baud Rate &
Download value change)

- 19 -
TROUBLESHOOTING
1. No power
(1) Symptom
1) Doesn't minute discharge at module.
2) Non does not come in into the front LED.
(2) Check follow
Plug in power cord
No
Yes
Is plug in power cord?
Connect cable.
No
Is connect the Line
Filter and Power
Board Cable?
Replace fuse.
No
Is normal the
Fuse(F100) on Power
Board?
Connect Cable.
After remove the cable connect to
Power Board (except the SC100
connection cable), authorizes the
AC voltage marking on manual.
When ST-BY 5V does not operate,
replace Power Board.
No
Is connect the Power
Board and 13P of VSC
Board Cable?
Yes
Yes
Yes

- 20 -
2. Protect mode
(1) Symptom
1) After once shining, it does not discharge minutely from module.
2) The relay falls.(The sound is audible “Click”.)
3) It is converted with the color where the front LED is red from green.
(2) Check follow
Is normal the Power
Board?
Replace Power Board.
Is output the normality Low/High
voltage except Stand-by 5V?
Yes
No No
Is normal the each
connector? Replace connector.
After connecting well each connector,
the normality it operates?
Yes
No No
Is normal the VSC
Board?
After remove P900, P901
normal operation:
Replace VSC Board
Is normal the output voltage after
remove P900, P901 of VSC Board?
No Yes