JVC LT-42S90B Schematic

SERVICE MANUAL

YA604<Rev.001>20084SERVICE MANUAL

LT-42S90B/B, LT-42S90B/G,

WIDE LCD TELEVISION

LT-42S90B

No.YA597: LT-42DS9 series No.YA598: LT-42S90BU

/L, LT-42S90B/S

BASIC CHASSIS

FT4

TABLE OF CONTENTS

1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

2 SPECIFIC SERVICE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16

5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20

No.YA604<Rev.001>

2008/4

SPECIFICATION

Items Contents

Dimensions ( W × H × D ) 98.1 cm × 67.3 cm × 27.5 cm [Included stand]

98.1 cm × 62.7 cm × 7.5 cm [TV only]

Mass 23.3 kg [Included stand]

19.3 kg [TV only]

Power Input AC220V - AC240 V, 50 Hz

Power Consumption 183 W (Standby: 0.5 W)

TV RF System CCIR (B/G, I, D/K, L)

Colour System PAL

SECAM NTSC 3.58/4.43 [EXT only]

Stereo System NICAM (B/G, I, D/K, L), A2 (B/G, D/K)

Receiving Frequency VHF: 47MHz - 470MHz

UHF: 470 MHz - 862 MHz CATV: 116MHz - 172MHz / 220MHz - 469MHz

Intermediate Frequency

Colour Sub Carrier Frequency

Teletext System FLOF (Fastext level 2.5)

LCD Panel 42V-inch wide aspect (16 : 9)

Screen Size Diagonal : 105 cm (H: 93.0 cm × V: 52.3 cm) Display Pixels Horizontal : 1920 dots × Vertical : 1080 dots (FULL HD)

Audio Power Output 10 W + 10 W

Speaker 4.5 cm × 13.0 cm, oblique type × 2 Aerial Terminal (VHF/UHF) 75 Ω unbalanced, coaxial EXT-1 / EXT-2 (Input / Output) 21-pin Euro connector (SCART socket ) × 2

EXT-3 (Input) Component Video

750p / 1125i / 1125p

625p / 525p / 625i / 525i

EXT-4 / EXT-5 / EXT-6 (HDMI Input)

Audio Output 500mV (rms), Low impedance, RCA pin jack × 2 Headphone 3.5 mm stereo mini jack × 1 Remote Control Unit RM-C1932 (AA/R6 dry cell battery × 2)

VIF 38.9MHz (B/G, I, D/K, L)

SIF 33.4MHz (5.5MHz :B/G)

32.9MHz (6.0MHz :I)

32.4MHz (6.5MHz :D/K)

PAL 4.43MHz

SECAM 4.40625MHz / 4.25MHz

NTSC 3.58MHz / 4.43MHz

TOP WST(World Standard system)

RCA pin jack × 3 Y : 1 V (p-p) (Sync signal: ±0.35V(p-p), 3-value sync.), 75Ω Pb/Pr : ±0.35V(p-p), 75 Ω Y : 1 V (p-p), Positive (Negative sync.), 75 Ω

Cb/Cr : 0.7V(p-p), 75 Ω Video 1V (p-p), Positive (Negative sync provided), 75 Ω, RCA pin jack × 1 Audio 500 mV(rms) (-4dBs), high impedance, RCA pin jack × 2

HDMI 2-row 19pin connector × 3

(Digital-input terminal is not compatible with picture signals of personal computer) Video

Supported format: 525i/625i/525p/625p/750p/1125i/1125p(24/50/60) Audio

PCM 2ch

Design & specifications are subject to change without notice.

1-2 (No.YA604<Rev.001>)

SECTION 1

PRECAUTION

1.1 SAFETY PRECAUTIONS

(1) The design of this product contains special hardware,

many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer. Replacement parts must be identical to those used in the original circuits. Service should be performed by qualified personnel only.

(2) Alterations of the design or circuitry of the products should

not be made. Any design alterations or additions will void the manufacturer's warranty and will further relieve the manufacturer of responsibility for personal injury or property damage resulting therefrom.

(3) Many electrical and mechanical parts in the products have

special safety-related characteristics. These characteristics are often not evident from visual inspection nor can the protection afforded by them necessarily be obtained by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in the parts list of Service manual. Electrical components

having such features are identified by shading on the schematics and by ( ) on the parts list in Service manual. The use of a substitute replacement which does

not have the same safety characteristics as the recommended replacement part shown in the parts list of Service manual may cause shock, fire, or other hazards.

(4) Don't short between the LIVE side ground and

ISOLATED (NEUTRAL) side ground or EARTH side ground when repairing.

Some model's power circuit is partly different in the GND. The difference of the GND is shown by the LIVE : ( ) side GND, the ISOLATED (NEUTRAL) : ( ) side GND and EARTH : ( ) side GND. Don't short between the LIVE side GND and ISOLATED (NEUTRAL) side GND or EARTH side GND and never measure the LIVE side GND and ISOLATED (NEUTRAL) side GND or EARTH side GND at the same time with a measuring apparatus (oscilloscope etc.). If above note will not be kept, a fuse or any parts will be broken.

(5) When service is required, observe the original lead dress.

Extra precaution should be given to assure correct lead dress in the high voltage circuit area. Where a short circuit has occurred, those components that indicate evidence of overheating should be replaced. Always use the manufacturer's replacement components.

(6) Isolation Check (Safety for Electrical Shock Hazard)

After re-assembling the product, always perform an isolation check on the exposed metal parts of the cabinet (antenna terminals, video/audio input and output terminals, Control knobs, metal cabinet, screw heads, earphone jack, control shafts, etc.) to be sure the product is safe to operate without danger of electrical shock.

a) Dielectric Strength Test

The isolation between the AC primary circuit and all metal parts exposed to the user, particularly any exposed metal part having a return path to the chassis should withstand a voltage of 3000V AC (r.m.s.) for a period of one second. (. . . . Withstand a voltage of 1100V AC (r.m.s.) to an appliance rated up to 120V, and 3000V AC (r.m.s.) to an appliance rated 200V or more, for a period of one second.) This method of test requires a test equipment not generally found in the service trade.

b) Leakage Current Check

Plug the AC line cord directly into the AC outlet (do not use a line isolation transformer during this check.). Using a "Leakage Current Tester", measure the leakage current from each exposed metal part of the cabinet, particularly any exposed metal part having a return path to the chassis, to a known good earth ground (water pipe, etc.). Any leakage current must not exceed 0.5mA AC (r.m.s.). However, in tropical area, this must not exceed 0.2mA AC (r.m.s.).

Alternate Check Method

Plug the AC line cord directly into the AC outlet (do not use a line isolation transformer during this check.). Use

an AC voltmeter having 1000Ω per volt or more sensitivity in the following manner. Connect a 1500Ω 10W resistor paralleled by a 0.15µF AC-type capacitor

between an exposed metal part and a known good earth ground (water pipe, etc.). Measure the AC voltage across the resistor with the AC voltmeter. Move the resistor connection to each exposed metal part, particularly any exposed metal part having a return path to the chassis, and measure the AC voltage across the resistor. Now, reverse the plug in the AC outlet and repeat each measurement. Any voltage measured must not exceed 0.75V AC (r.m.s.). This corresponds to

0.5mA AC (r.m.s.). However, in tropical area, this must not exceed 0.3V AC (r.m.s.). This corresponds to 0.2mA AC (r.m.s.).

AC VOLTMETER (HAVING 1000 /V, OR MORE SENSITIVITY)

0.15 F AC-TYPE

GOOD EARTH GROUND

1500 10W

PLACE THIS PROBE ON EACH EXPOSED ME TAL PAR T

(No.YA604<Rev.001>)1-3

1.2 INSTALLATION

1.2.1 ATTACH THE STAND TO THE TV

When installing the unit on the floor, it is required to attach the supplied stand. To attach the stand to the TV, follow the procedure below.

To prevent scratches on the panel, lay a piece of soft cloth on an even platform and place the TV onto it.

1.2.3 INSTALLATION REQUIREMENTS

Ensure that the minimal distance is maintained, as specified below, between the unit with and the surrounding walls, as well as the floor etc.Install the unit on stable flooring or stands.Take precautionary measures to prevent the unit from tipping in order to protect against accidents and earthquakes.

200mm

150mm 150mm

50mm

*The drawing may differ from the actual appearance.

1.2.4 INSTALLATION REQUIREMENTS

To ensure safety in an emergency such as an earthquake, and to prevent accidents, ensure that measures are taken to prevent the TV dropping or falling over.

1.2.2 HEAT DISSIPATION

If the heat dissipation vent behind this unit is blocked, cooling efficiency may deteriorate and temperature inside the unit will rise. The temperature sensor that protects the unit will be activated when internal temperature exceeds the pre-determined level and power will be turned off automatically.Therefore, please make sure pay attention not to block the heat dissipation vent as well as the ventilation outlet behind the unit and ensure that there is room for ventilation around it.

VENTILATION HOLE

*The drawing may differ from the actual appearance.

It fixes in a band.

TV STAND

*The drawing may differ from the actual appearance.

1.2.5 NOTES ON HANDLING

When taking the unit out of a packing case, do not grasp the upper part of the unit. If you take the unit out while grasping the upper part, the LCD PANEL may be damaged because of a pressure. Instead of grasping the upper part, put your hands on the lower backside or sides of the unit.

1-4 (No.YA604<Rev.001>)

1.3 HANDLING LCD PANEL

1.3.1 PRECAUTIONS FOR TRANSPORTATION

When transporting the unit, pressure exerted on the internal LCD panel due to improper handling (such as tossing and dropping) may cause damages even when the unit is carefully packed. To prevent accidents from occurring during transportation, pay careful attention before delivery, such as through explaining the handling instructions to transporters. Ensure that the following requirements are met during transportation, as the LCD panel of this unit is made of glass and therefore fragile:

(1) USE A SPECIAL PACKING CASE FOR THE LCD PANEL

When transporting the LCD panel of the unit, use a special packing case (packing materials). A special packing case is used when a LCD panel is supplied as a service spare part.

(2) ATTACH PROTECTION SHEET TO THE FRONT

Since the front (display part) of the panel is vulnerable, attach the protection sheet to the front of the LCD panel before transportation. Protection sheet is used when a LCD panel is supplied as a service spare part.

(3) AVOID VIBRATIONS AND IMPACTS

The unit may be broken if it is toppled sideways even when properly packed. Continuous vibration may shift the gap of the panel, and the unit may not be able to display images properly. Ensure that the unit is carried by at least 2 persons and pay careful attention not to exert any vibration or impact on it.

(4) DO NOT PLACE EQUIPMENT HORIZONTALLY

Ensure that it is placed upright and not horizontally during transportation and storage as the LCD panel is very vulnerable to lateral impacts and may break. During transportation, ensure that the unit is loaded along the traveling direction of the vehicle, and avoid stacking them on one another. For storage, ensure that they are stacked in 2 layers or less even when placed upright.

1.3.3 PRECAUTIONS FOR REPLACEMENT OF EXTERIOR PARTS

Take note of the following when replacing exterior parts (REAR COVER, FRONT PANEL, etc.):

(1) Do not exert pressure on the front of the LCD panel (filter

surface). It may cause irregular colour.

(2) Pay careful attention not to scratch or stain the front of the

LCD panel (filter surface) with hands.

(3) When replacing exterior parts, the front (LCD panel) should

be placed facing downward. Place a mat, etc. underneath to avoid causing scratches to the front (filter surface).

1.3.4 HOW TO CHECK THE OPERATING TIME

This model has a function to count and record the LCD panel operating time. The operating time can be checked in the following procedure.

• Maximum count time = 131072 hours

(1) Press the [INFORMATION] key and [MUTING] key

simultaneously, then enter the SERVICE MODE. (2) Press the [2] key SELF CHECK MODE. (3) The operating time of the LCD panel is displayed in 6-digit

decimal number.(Refer to the below figure)

SERVICE MODE SCREEN

Service Menu

1.Adjust

2.Self Check

3.I2C Stop

Press [2] key

1.3.2 OPTICAL FILTER (ON THE FRONT OF THE LCD PANEL)

(1) Avoid placing the unit under direct sunlight over a

prolonged period of time. This may cause the optical filter to deteriorate in quality and colour.

(2) Clean the filter surface by wiping it softly and lightly with a

soft and lightly fuzz cloth (such as outing flannel).

(3) Do not use solvents such as benzene or thinner to wipe the

filter surface. This may cause the filter to deteriorate in quality or the coating on the surface to come off. When cleaning the filter, usually use the neutral detergent diluted with water. When cleaning the dirty filter, use water-diluted ethanol.

(4) Since the filter surface is fragile, do not scratch or hit it with

hard materials. Be careful enough not to touch the front surface, especially when taking the unit out of the packing case or during transportation.

SELF CHECK MODE SCREEN (Page 1)

Self Check

LOB 1

MEM 2 AIO 1

TUN 1 HDM 1

TOS 1

HOUR XXXXXX

Redkey2Page

i:EXIT

*When the power is turned off with the remote control unit or the power

button of the main unit, the count restarts from the turn off time.

*When the power is turned off by disconnecting the power cord from the

AC outlet, the recorded time count less than 2 hours is not counted.

1.3.5 HOW TO RESET THE OPERATING TIME

When the LCD panel unit is replaced, be sure to reset the operating time in the following method.

(1) Press the [INFORMATION] key and [MUTING] key

simultaneously, then enter the SERVICE MODE. (2) Press the [9] key, then start the SHIPPING setting. (3) The power of the UNIT is turned off automatically, and the

OPERATING TIME is reset.

The operating time is displayed.

(No.YA604<Rev.001>)1-5

SECTION 2

SPECIFIC SERVICE INSTRUCTIONS

2.1 FEATURES

SUPER SLIM design

The screen surround itself is also very slim, so overall you have a TV that takes up far less room and is much more like a picture frame.

FULL HD

Full HD models deliver superbly detailed image reproduction of more than 2 megapixels (1920 x 1080), which represents double the resolution offered by WXGA panels.

2.2 MAIN DIFFERENCE LIST

HDMI INPUT

By connecting a HDMI compatible device, high definition pictures can be displayed on your TV in their digital form.

DIGITAL VNR

This function cuts down the amount of noise in the original picture.

MaxxBass

This function emphasizes the bass sound.

3D Cinema Sound

You can enjoy sounds with a wider ambience.

ITEM

LT-42S90B/B LT-42S90B/G LT-42S90B/L LT-42S90B/S

MODELS

POWER CORD Round 2PIN type EU Type (2 Pins) Round 2PIN type UK 3PIN type

2.3 21-PIN EURO CONNECTOR (SCART) : EXT-1 / EXT-2

Pin No. Signal designation Matching value EXT-1 EXT-2

1 AUDIO R output 500mV(rms) (Nominal), Low impedance Used (TV OUT) Used (LINE OUT)

2 AUDIO R input 500mV(rms) (Nominal), High impedance Used (R1) Used (R2)

3 AUDIO L output 500mV(rms) (Nominal), Low impedance Used (TV OUT) Used (LINE OUT)

4 AUDIO GND Used Used

5 GND (B) Used Used

6 AUDIO L input 500mV(rms) (Nominal), High impedance Used (L1) Used (L2)

7 B input 700mV

8 FUNCTION SW

(SLOW SW)

9 GND (G) Used Used

10 SCL Not used Used (SCL2)

11 G input 700mV

12 SDA Not used Used (SDA2)

13 GND (R) Used Used

14 GND (YS) Used Not used

15 R / C input R : 700mV

16 Ys input (FAST SW) Low : 0V-0.4V, High : 1V-3V, 75Ω Used Not used

17 GND (VIDEO output) Used Used

18 GND (VIDEO input) Used Used

19 VIDEO output 1V

20 VIDEO / Y input 1V

21 COMMON GND Used Used

Low : 0V-3V High : 8V-12V, High impedance

C : 300mV

(P-P)

, 75Ω Used Not used

(B-W)

Used Used

, 75Ω Used Not used

(B-W)

, 75Ω

(B-W)

, 75Ω

(P-P)

(Negative sync), 75Ω Used (TV OUT) Used (LINE OUT) (Negative sync), 75Ω Used Used

Used (R) Used (C2)

(P-P= Peak to Peak, B-W= Blanking to white peak)

[Pin assignment]

20 18 16 14 12 10 8 6 4 2

21 19 17 15 13 11 9 7 5 3 1

1-6 (No.YA604<Rev.001>)

2.4 TECHNICAL INFORMATION

2.4.1 LCD PANEL

This unit uses the flat type panel LCD (Liquid Crystal Display) panel that occupies as little space as possible, instead of the conventional CRT (Cathode Ray Tube), as a display unit. Since the unit has the two polarizing filter that are at right angles to each other, the unit adopts "normally black" mode, where light does not pass through the polarizing filter and the screen is black when no voltage is applied to the liquid crystals.

2.4.1.1 SPECIFICATIONS

The following table shows the specifications of this unit.

Item Specifications

Maximum dimensions ( W × H × D )

96.3 cm × 55.6 cm × 2.9 cm

Weight 11.0 kg

Effective screen size Diagonal: 106.7 cm (H: 93.0 cm × V: 52.3 cm)

Aspect ratio 16 : 9

Drive device / system a-Si-TFT active matrix system

Resolution Horizontally 1920 × Vertically 1080 × RGB <FULL HD> 6220800 dots in total

Pixel pitch (pixel size) Horizontally: 0.4845 mm, Vertically: 0.4845 mm

Displayed colour 16777216 colours 256 colours for R G and B

Brightness 500 cd/m

Contrast ratio 1500 : 1

Response time 6.5 ms

View angle (Horizontally) 178° View angle (Vertically) 178°

Surface polarizer Anti-Glare type Low reflective coat

Colour filter Vertical stripe

Backlight Cold cathode fluorescent lamp × 22

Power supply voltage in LCD 12 V

Power supply voltage in inverter

24 V

Panel interface system LVDS (Low Voltage Differential Signaling)

2.4.1.2 PIXEL FAULT

There are three pixel faults - bright fault, dark fault and flicker fault - that are respectively defined as follows.

 BRIGHT FAULT

In this pixel fault, a cell that should not light originally is lighting on and off. For checking this pixel fault, input ALL BLACK SCREEN and find out the cell that is lighting on and off.

 DARK FAULT

In this pixel fault, a cell that should light originally is not lighting or lighting with the brightness twice as brighter as originally lighting. For checking this pixel fault, input 100% of each R/G/B colour and find out the cell that is not lighting.

 FLICKER FAULT

In the pixel fault, a cell that should light originally or not light originally is flashing on and off. For checking this pixel fault, input ALL BLACK SCREEN signal or 100% of each RGB colour and find out the cell that is flashing on and off.

(No.YA604<Rev.001>)1-7

2.4.2 MAIN CPU PIN FUNCTION [IC7001

Pin Pin name I/O Function

1KEY1 I 2 ECO SENSER I Eco sensor detection 3 VDD33_GPIO - 3.3V power supply 4 SLOW1 I EXT-1 SLOW detection 5 SLOW2 I EXT-2 SLOW detection 6 AFC1 I AFT voltage for VHF/UHF tuner 7 AGC I RF AGC voltage for VHF/UHF tuner 8 GND - GND

9 VDD33_CADC - 3.3V power supply 10 MONITOR_OUT O Video for EXT-2 11 VDD33_AFE - 3.3V power supply 12 VOUT2 O Not used

VDD12_ADC_1234

13 14 VOUT3 O Not used 15 GND - GND 16 TV_CV I Video for VHF/UHF tuner 17 GND - GND 18 E1_CV I Video for EXT-1

VDD12_ADC_1234

19 20 E2_CV/Y I Video/Y for EXT-2 21 GND - GND 22 AGND1234 I LPF setting 23 VDD33_AFE - 3.3V power supply 24 IDTV_CV I Not used

VDD12_ADC_1234

25 26 IDTV_CR I Cr for digital tuner 27 GND - GND 28 IDTV_Y I Y for digital tuner 29 GND - GND 30 SC_FB1 I Ys for EXT-1

VDD12_ADC_1234

31 32 IDTV_CB I Not used 33 GND - GND 34 SC_R1 I R for EXT-1 35 VDD33_AREF - 3.3V power supply 36 SC_G1 I G for EXT-1

VDD12_ADC_5678

37 38 SC_B1 I B for EXT-1 39 GND - GND 40 AGND5678 I LPF setting 41 GND - GND 42 E2_C I C for EXT-2

VDD12_ADC_5678

43 44 VIN16 I Not used 45 GND - GND 46 VIN17 I Not used 47 VDD33_AREF - 3.3V power supply 48 VIN18 I Not used

VDD12_ADC_5678

49 50 E3_PR I Pr for EXT-3 51 GND - GND 52 E3_Y I Y for EXT-3 53 GND - GND 54 E3_PB I Pb for EXT-3

VDD12_ADC_5678

55 56 VIN22 I Not used 57 GND - GND 58 VDD_CORE - 1V power supply 59 GND - GND 60 SIF_INM I SIF for VHF/UHF tuner 61 TU_SIF I SIF for VHF/UHF tuner 62 VDD12_SIFADC - 1.25V power supply 63 LINE_OUT1R O Audio for EXT-1 64 LINE_OUT1L O Audio for EXT-1 65 TU_R O Audio for EXT-2 or Audio 66 TU_L O Audio for EXT-2 or Audio 67 R_AUSW I Audio 68 L_AUSW I Audio 69 VDD33_AAU - 3.3V power supply

Key scan for side control (POWER/VOL/UP/DOWN)

- 1.25V power supply

: MAIN PWB]

Pin Pin name I/O Function

70 LINE_IN3R I Not used 71 LINE_IN3L I Not used 72 GND - GND 73 LINE_IN2R I Not used 74 LINE_IN2L I Not used 75 GND - GND 76 LINE_IN1R I Not used 77 LINE_IN1L I Not used 78 VREFAU I Reference voltage setting 79 HP_R O Audio for headphone 80 HP_L O Audio for headphone 81 MAIN_OUT_SUB O Not used 82 M_R O Audio for speaker 83 M_L O Audio for speaker 84 GND - GND

VDD10_HDMI1+2

85 86 HMDI1_RXCN I TMDS clock for HDMI 87 HMDI1_RXCP I TMDS clock for HDMI 88 GND - GND

VDD33_HDMI1+2

89 90 HDMI1_RX0N I TMDS data for HDMI 91 HDMI1_RX0P I TMDS data for HDMI 92 GND - GND 93

VDD10_HDMI1+2 94 HDMI1_RX1N I TMDS data for HDMI 95 HDMI1_RX1P I TMDS data for HDMI 96 GND - GND

VDD33_HDMI1+2

97 98 HDMI1_RX2N I TMDS data for HDMI 99 HDMI1_RX2P I TMDS data for HDMI

100 GND - GND

VDD10_HDMI1+2

101 102 VDD_CORE - 1V power supply 103 GND - GND

VDD10_HDMI1+2

104 105 HMDI2_RXCN I Not used 106 HMDI2_RXCP I Not used 107 GND - GND 108

VDD33_HDMI1+2

109 HDMI2_RX0N I Not used 110 HDMI2_RX0P I Not used 111 GND - GND

VDD10_HDMI1+2

112 113 HDMI2_RX1N I Not used 114 HDMI2_RX1P I Not used 115 GND - GND

VDD33_HDMI1+2

116 117 HDMI2_RX2N I Not used 118 HDMI2_RX2P I Not used 119 GND - GND 120

VDD10_HDMI1+2

121 VDD25_DRAM - 2.5V power supply 122 DRAM_VREF I Reference voltage setting 123 VDD25_DRAM - 2.5V power supply 124 VDD25_DRAM - 2.5V power supply 125 VDD25_DRAM - 2.5V power supply 126 RX_DTV O Not used 127 DIN_HOTP1 O 128 AUDIO_MUTE O 129 VDD33_GPIO - 3.3V power supply 130 LB_PRO I 131 P3.2 I L fixed 132 HM_SDA I/O Data for I2C bus (for HDMI) 133 HM_SCL O Clock for I2C bus (for HDMI) 134 HM_HPLUG2 O 135 HM_HPLUG3 O 136 STATUS I Not used 137 ID_RESET O Not used 138 IRQ O Not used

- 1V power supply

- 3.3V power supply

- 1V power supply

- 3.3V power supply

- 1V power supply

- 3.3V power supply

- 1V power supply

- 3.3V power supply

- 1V power supply

Hotplug error detection for HDMI connector-1 [Error = L] Speaker/headphone output muting [Muting = H]

Power abnormality detection [Emergent = H]

Hotplug error detection for HDMI connector-2 [Error = L] Hotplug error detection for HDMI connector-3 [Error = L]

1-8 (No.YA604<Rev.001>)

Pin Pin name I/O Function 139 TX_DTV I Not used 140 P4.6 I/O Not used 141 P4.7 I/O Not used 142 BL_ON O 143 LCD_POW O

Power on/off control for back-light [ON = L]

Power on/off control for LCD drive [ON = H] 144 VDD33_VIPA - 3.3V power supply 145 TV_LINK_IN I Not used 146 TV LINK_OUT O Not used 147 P2.4 I/O Not used 148 P2.5 I/O Not used 149 P2.6 I/O Not used 150 P2.7 I/O Not used 151 NC I L fixed 152 NC I L fixed 153 NC - GND 154 NC I L fixed 155 P3.0 I L fixed 156 P3.1 I L fixed 157 NC I L fixed 158 VDD33_VIPA - 3.3V power supply 159 NC I L fixed 160 NC I L fixed 161 NC I L fixed 162 VDD33_VIPA - 3.3V power supply 163 NC I L fixed 164 NC I L fixed 165 NC I L fixed 166 SDA0 I/O Data for I 167 SCL0 O Clock for I

C bus (for E2PROM)

C bus (for E2PROM) 168 PFC O Power on/off control for PFC [ON = L] 169 MAIN_POWER O

Power on/off control for main power [ON = L] 170 VDD - 1V power supply 171 TCLK I Clock for JTAG interface 172 TDI I Data for JTAG interface 173 TDO O Data for JTAG interface 174 TMS I Control signal for JTAG interface 175 GND - GND 176 GND - GND 177 GND - GND 178 GND - GND 179 GND - GND 180 GND - GND 181 VDD33_DAU - 3.3V power supply 182 NC - Not used 183 NC I L fixed 184 NC I L fixed 185 NC I L fixed 186 NC - Not used 187 NC - Not used 188 PWM_DIM O

PWM dimming control for back-light inverter 189 VDD25_PIP - 2.5V power supply 190 DC_DIM O

Not used: DC dimming control for back-light inverter 191 PCS6 O Not used 192 PCS5 O Not used 193 VDD25_PIP - 2.5V power supply 194 PCS4 O Not used 195 PCS3 O Not used 196 VDD25_PIP - 2.5V power supply 197 PCS2 O Not used 198 PCS1 O Not used 199 VDD25_DRAM - 2.5V power supply 200 VDD25_DRAM - 2.5V power supply 201 VDD25_DRAM - 2.5V power supply 202 VDD10_DLL - 1V power supply 203 VDD25_DRAM - 2.5V power supply 204 TE2+ O LVDS data for LCD panel 205 TE2- O LVDS data for LCD panel 206 VDD25_VOPA - 2.5V power supply 207 TD2+ O LVDS data for LCD panel 208 TD2- O LVDS data for LCD panel

Pin Pin name I/O Function 209 GND - GND 210 TCLK2+ O LVDS clock for LCD panel 211 TCLK2- O LVDS clock for LCD panel 212 VDD25_VOPA - 2.5V power supply 213 TC2+ O LVDS data for LCD panel 214 TC2- O LVDS data for LCD panel 215 GND - GND 216 TB2+ O LVDS data for LCD panel 217 TB2- O LVDS data for LCD panel 218 VDD25_VOPA - 2.5V power supply 219 TA2+ O LVDS data for LCD panel 220 TA2- O LVDS data for LCD panel 221 GND - GND 222 GND - GND 223 VDD25_PLL - 2.5V power supply 224 VDD33_FLASH - 3.3V power supply 225 VDD10_PLL - 1V power supply 226 TE1+ O LVDS data for LCD panel 227 TE1- O LVDS data for LCD panel 228 VDD25_VOPA - 2.5V power supply 229 TD1+ O LVDS data for LCD panel 230 TD1- O LVDS data for LCD panel 231 GND - GND 232 TCLK1+ O LVDS clock for LCD panel 233 TCLK1- O LVDS clock for LCD panel 234 VDD25_VOPA - 2.5V power supply 235 TC1+ O LVDS data for LCD panel 236 TC1- O LVDS data for LCD panel 237 GND - GND 238 TB1+ O LVDS data for LCD panel 239 TB1- O LVDS data for LCD panel 240 VDD25_VOPA - 2.5V power supply 241 TA1+ O LVDS data for LCD panel 242 TA1- O LVDS data for LCD panel 243 VDD_CORE - 1V power supply 244 VSENSE I Not used 245 VDD10 - 1V power supply 246 GND - GND 247 XTALIN I X'tal oscillation for CPU system clock 248 XTALOUT O X'tal oscillation for CPU system clock 249 VDD33_GPIO - 3.3V power supply 250 RESET I CPU reset [Reset = L] 251 SDA1 I/O Data for I 252 SCL1 O

Clock for

C bus (for tuner/MaxxBass)

I2C

bus (for tuner/MaxxBass) 253 VDD33_STDB - 3.3V power supply 254 VDD10_STDB - 1V power supply 255 REMOCON I Remote control sensor 256 HM_POWER I Power status detect for HDMI

(No.YA604<Rev.001>)1-9

SECTION 3

DISASSEMBLY

3.1 CAUTION AT DISASSEMBLY

• Make sure that the power cord is disconnected from the outlet.

• Pay special attention not to break or damage the parts.

• Make sure that there is no bent or stain on the connectors before inserting, and firmly insert the connectors.

• Be sure to reattach the wire clamps removed during the procedure to the original positions. (Attaching the wire clamps in wrong positions may affect the performance.)

REFERENCE:

When removing each board, remove the connector if necessary. The operation is easier if you write down the connection points (connector numbers) of the connector. For connection of each board, refer to the "WIRING DIAGRAM" of the Standard Circuit Diagram.

3.2 DISASSEMBLY PROCEDURE

3.2.1 REMOVING THE REAR COVER (Fig.3-1)

(1) Remove the 1 screw [A]. (2) Remove the STAND COVER. (3) Remove the 1 screw [B]. (4) Remove the POWER CORD COVER. (5) Remove the POWER CORD. (6) Remove the JACK COVER. (7) Remove the 2 hooks [a], 10 screws [C], 5 screws [D], 5

screws [E] and 1 screw [F].

(8) Remove the REAR COVER.

3.2.2 REMOVING THE POWER UNIT (Fig.3-1)

• Remove the STAND COVER.

• Remove the REAR COVER.

• Remove the POWER CORD. (1) Remove the 6 screws [G]. (2) Remove the POWER UNIT.

3.2.3 REMOVING THE MAIN PWB (Fig.3-1)

• Remove the STAND COVER.

• Remove the REAR COVER. (1) Remove the 1 screw [H]. (2) Remove the TERMINAL BASE. (3) Remove the 7 screws [J]. (4) Remove the MAIN PWB.

3.2.6 REMOVING THE HP/USB PWB (Fig.3-1)

• Remove the STAND COVER.

• Remove the REAR COVER. (1) Remove the 1 screw [N]. (2) Remove the HP/USB PWB.

3.2.7 REMOVING THE LED PWB, LED LENS (Fig.3-1)

• Remove the STAND COVER.

• Remove the REAR COVER. (1) Remove the 1 screw [P]. (2) Remove the LED PWB. (3) Remove the LED LENS.

3.2.8 REMOVING THE SPEAKER (Fig.3-1)

• Remove the STAND COVER.

• Remove the REAR COVER. (1) Remove the 4 screws [Q]. (2) Remove the SPEAKER HOLDER. (3) Remove the 4 screws [R]. (4) Remove the SPEAKER.

3.2.9 REMOVING THE STAND ASS’Y (Fig.3-1)

• Remove the STAND COVER. (1) Remove the 4 screws [S]. (2) Remove the STAND.

3.2.4 REMOVING THE CAPSENS PWB (Fig.3-1)

• Remove the STAND COVER.

• Remove the REAR COVER. (1) Remove the CAPSENS PWB by carefully peeling off the

double faced tape.

3.2.5 REMOVING THE IR PWB (Fig.3-1)

• Remove the STAND COVER.

• Remove the REAR COVER. (1) Remove the 1 screw [M]. (2) Remove the IR PWB.

1-10 (No.YA604<Rev.001>)

3.2.10 REMOVING THE LCD PANEL UNIT (Fig.3-1)

• Remove the STAND COVER.

• Remove the REAR COVER.

• Remove the STAND. (1) Remove the 3 screws [T] and 2 screws [U]. (2) Remove the STAND SUPPORT. (3) Remove the 8 screws [V]. (4) Remove the BACK BRACKET. (5) Remove the 4 screws [W]. (6) Remove the MAIN BASE. (7) Remove the 6 screws [X]. (8) Slide the SIDE BRACKET in the direction of the arrow to

remove it.

(9) Remove the 4 screws [Y].

(10) Slide the TOP BRACKET in the direction of the arrow to

remove it.

(11) Lift up the LCD PANEL UNIT to remove it.

POWER CORD

REAR COVER

POWER CORD COVER

JACK COVER

STAND COVER

BACK BRACKET

POWER UNIT

TOP BRACKET

MAIN BASE

TOP BRACKET

BACK BRACKET

MAIN PWB

TERMINAL BASE

SIDE BRACKET

SPEAKER HOLDER

HP/USB PWB

STAND

SPEAKER

SIDE BRACKET

FRONT PANEL

FRONT

CAPSENS PWB

Fig.3-1

LED PWB

LED LENS

IR PWB

STAND SUPPORT

(No.YA604<Rev.001>)1-11

3.2.11 REMOVING THE LCD CONTROL PWB (Fig.3-2)

• Remove the STAND COVER.

• Remove the REAR COVER.

• Remove the MAIN BASE. (1) Remove the 4 screws [A]. (2) Remove the LCD CONTROL PWB COVER. (3) Remove the LCD CONTROL PWB.

INVERTER PWB COVER

3.2.12 REMOVING THE INVERTER PWB (Fig.3-2)

• Remove the STAND COVER.

• Remove the REAR COVER.

• Remove the SIDE BRACKET. (1) Remove the 6 screws [B]. (2) Remove the INVERTER PWB COVER. (3) Remove the INVERTER PWB. (4) Follow the same steps when removing the other

INVERTER PWB.

INVERTER PWB COVER

LCD CONTROL PWB COVER

INVERTER PWB (MASTER)

LCD CONTROL PWB

INVERTER PWB (SLAVE)

LCD PANEL UNIT

Fig.3-2

1-12 (No.YA604<Rev.001>)

3.3 MEMORY IC REPLACEMENT

• This model uses the memory IC.

• This memory IC stores data for proper operation of the video and drive circuits.

• When replacing, be sure to use an IC containing this (initial value) data.

3.3.1 MEMORY IC TABLE

Symbol Number of pins Mounting PWB Main content of data

IC7003

8-pin MAIN PWB Setting value of IC7001(MAIN CPU) is memorized.

3.3.2 MEMORY IC REPLACEMENT PROCEDURE

1. Power off

Switch off the power and disconnect the power plug from the AC outlet.

2. Replace the memory IC

Be sure to use the memory IC written with the initial setting values.

3. Power on

Connect the power plug to the AC outlet and switch on the power.

4. Receiving channel setting

Refer to the OPERATING INSTRUCTIONS and set the receive channels (Channels Preset) as described.

5. User setting

Check the user setting items according to the given in page later. Where these do not agree, refer to the OPERATING INSTRUCTIONS and set the items as described.

6. SERVICE MODE setting

Verify what to set in the SERVICE MODE, and set whatever is necessary (Fig.3-3). Refer to the SERVICE ADJUSTMENT for setting.

3.3.3 SERVICE MODE SETTING

SERVICE MODE SCREEN

SERVICE MODE SCREEN

Service Menu

1.Adjust

2.Self Check

3.I2C Stop

Press [1] key

ADJUST MODE SCREEN

Adjust PAL BG

1.SC ADJ 15 SC DEV : +00

OK:Store i:Exit

SETTING ITEM

Setting mode Setting items Settings

1.ADJUST 1.SC ADJ. Adjust

2.R DRIVE Adjust

3.G DRIVE Adjust

4.B DRIVE Adjust

5.CUTOFF R Fixed [Do not adjust]

6.CUTOFF G Fixed [Do not adjust]

7.CUTOFF B Fixed [Do not adjust]

8.COLOUR Fixed [Do not adjust]

9.HUE Fixed [Do not adjust]

10.CONT. Fixed [Do not adjust]

11.BRIGHT2 Fixed [Do not adjust]

12.SHARP Fixed [Do not adjust]

13.CORING Fixed [Do not adjust]

Fig.3-3

(No.YA604<Rev.001>)1-13

3.3.4 SETTINGS OF FACTORY SHIPMENT

3.3.4.1 BUTTON OPERATION 3.3.4.2 REMOTE CONTROL DIRECT OPERATION

Setting item Setting position

POWER Off

CHANNEL PR1

VOLUME 10

TV/AV TV

3.3.4.3 REMOTE CONTROL MENU OPERATION

(1) PICTURE

Setting item Setting position

Picture Mode Bright

Colour Temp. Cool

FEATURES

Digital VNR RF Auto

OTHER On

DigiPure On

Movie Theatre Off

Colour Management On

Picture Management On

Smart Picture On

Dynamic Backlight On

MPEG Noise Reduction On

Colour System TV Depends on PR/CH

EXT Auto

4:3 Auto Aspect Panoramic

CHANNEL PR1

VOLUME 10

ZOOM Auto

SUB POWER Off

VIDEO-3 COMPONENT / COMPOSITE

(3) FEATURES

Sleep Timer Off

Child Lock Off (ID:0000)

Blue Back On

Favourite Setting Blank

Power Lamp On

Eco Sensor Off

(4) SET UP

Auto Program TV Channel Automatically Set

Edit / manual Preset Ch Only

Language English

Ext Setting Ext-1

HDMI-1 Audio Setting Auto

Setting item Setting position

Component

Setting item Setting position

(2) SOUND

Setting item Setting position

STEREO / I•II Stereo sound

Bass Centre

Treble Centre

Balance Centre

Hyper Sound Off

MaxxBass Low

3D CINEMA SOUND

Sorrund Mid

Bass Boost Mid

Auto Volume Control Off

1-14 (No.YA604<Rev.001>)

3.4 REPLACEMENT OF CHIP COMPONENT

3.4.1 CAUTIONS

(1) Avoid heating for more than 3 seconds. (2) Do not rub the electrodes and the resist parts of the pattern. (3) When removing a chip part, melt the solder adequately. (4) Do not reuse a chip part after removing it.

3.4.2 SOLDERING IRON

(1) Use a high insulation soldering iron with a thin pointed end of it. (2) A 30w soldering iron is recommended for easily removing parts.

3.4.3 REPLACEMENT STEPS

1. How to remove Chip parts

2. How to install Chip parts

[Resistors, capacitors, etc.]

(1) As shown in the figure, push the part with tweezers and

alternately melt the solder at each end.

(2) Shift with the tweezers and remove the chip part.

[Transistors, diodes, variable resistors, etc.]

(1) Apply extra solder to each lead.

SOLDER

[Resistors, capacitors, etc.]

(1) Apply solder to the pattern as indicated in the figure.

(2) Grasp the chip part with tweezers and place it on the

solder. Then heat and melt the solder at both ends of the chip part.

[Transistors, diodes, variable resistors, etc.]

(1) Apply solder to the pattern as indicated in the figure. (2) Grasp the chip part with tweezers and place it on the

solder.

(3) First solder lead A as indicated in the figure.

(2) As shown in the figure, push the part with tweezers and

alternately melt the solder at each lead. Shift and remove the chip part.

NOTE :

After removing the part, remove remaining solder from the pattern.

(4) Then solder leads B and C.

(No.YA604<Rev.001>)1-15

SECTION 4

ADJUSTMENT

4.1 ADJUSTMENT PREPARATION

(1) This TV is adjusted by using REMOTE CONTROL UNIT. (2) The adjustment using the REMOTE CONTROL UNIT is made on the basis of the initial setting values. The setting values

which adjust the screen to the optimum condition can be different from the initial setting values.

(3) Make sure that connection is correctly made AC to AC power source. (4) Turn on the power of the TV and measuring instruments for warming up for at least 30 minutes before starting adjustments. (5) If the receive or input signal is not specified, use the most appropriate signal for adjustment. (6) Never touch the parts (such as variable resistors, transformers and condensers) not shown in the adjustment items of this service

adjustment.

4.2 PRESET SETTING BEFORE ADJUSTMENTS

Unless otherwise specified in the adjustment items, preset the following functions with the REMOTE CONTROL UNIT.

Setting item Settings position

PICTURE MODE STANDARD

PICTURE adjustments Centre

COLOUR TEMP. NORMAL

Colour Management Off

Picture Management Off

Smart Picture Off

Dynamic Backlight Off

Eco Sensor Off

4.3 MEASURING INSTRUMENT AND FIXTURES

• Signal generator (Pattern generator)[PAL]

• Remote control unit

4.4 ADJUSTMENT ITEMS

 VIDEO CIRCUIT

• COLOUR DECODER adjustment

• WHITE BALANCE (HIGH LIGHT) adjustment

4.5.2 HOW TO EXIT THE SERVICE MODE

Press the [MENU] key to exit the Service mode.

4.5.3 CHANGE AND MEMORY OF SETTING VALUE

SELECTION OF SETTING ITEM

• [FUNCTION /] key.

For scrolling up / down the setting items.

CHANGE OF SETTING VALUE (DATA)

• [FUNCTION /] key.

For scrolling up / down the setting values.

MEMORY OF SETTING VALUE (DATA)

Changed setting value is memorized by pressing [OK] key.

4.5.4 SERVICE MODE SELECT KEY LOCATION

MUTING

INFORMATION

4.5 BASIC OPERATION OF SERVICE MODE

4.5.1 HOW TO ENTER THE SERVICE MODE

(1) Press [INFORMATION] key and [MUTING] key on the

remote control unit simultaneously to enter the SERVICE MODE SCREEN.

SERVICE MODE SCREEN

Service Menu

1.Adjust

2.Self Check

3.I2C Stop

NOT USED

NOTE:

Before entering the SERVICE MODE, confirm that the setting of TV/STB/DVD/AUDIO mode is at the "TV" side. If the switches have not been properly set, you cannot enter the SERVICE MODE.”

1-16 (No.YA604<Rev.001>)

Refer to SECTION5

FUNCTION

4.5.5 ADJUSTMENT MODE

This mode is used to adjust the VIDEO CIRCUIT.

4.5.5.1 HOW TO ENTER THE ADJUSTMENT MODE

When the SERVICE MENU SCREEN of SERVICE MODE is displayed, press [1] key to enter the ADJUSTMENT MODE.

NOTE:

• When a number key other than the [1] key is pressed in the SERVICE MODE SCREEN, the other relevant screen may be displayed. This is not used in the adjustment procedure. Press the

[MENU] key to return to the SERVICE MODE SCREEN.

4.5.5.2 DESCRIPTION OF STATUS DISPLAY

SERVICE MODE SCREEN

Service Menu

1.Adjust

2.Self Check

3.I2C Stop

(1) SIGNAL SYSTEM

The signal displayed on the screen is displayed.

480 60i : 480i (Component) / HDMI 480i 576 50i : 576i (Component) / HDMI 576i 480 60p : 480p (Component) / HDMI 480p 480 60p VGA : HDMI 480p VGA 576 50p : 576p (Component) / HDMI 576p 720 50p : 720p 50Hz (Component) / HDMI 720p 50Hz 720 60p : 720p 60Hz (Component) / HDMI 720p 60Hz 1080 60i : 1080i 60Hz (Component) / HDMI 1080i 60Hz 1080 50i : 1080i 50Hz (Component) / HDMI 1080i 50Hz 1080 60p : 1080p 60Hz (Component) / HDMI 1080p 60Hz 1080 50p : 1080p 50Hz (Component) / HDMI 1080p 50Hz 1080 24p : HDMI 1080p 24Hz PAL BG : PAL 50Hz(Composite / S-video) SECAM : SECAM NTSC3.58 : NTSC3.58 NTSC4.43 : NTSC4.43 PAL 60 : PAL 60Hz(Composite / S-video) PAL M : PAL M PAL N : PAL N RGB 480i : RGB 480i RGB 576i : RGB 576i Undefined : Other than those above

Press [1] key

ADJUST MODE SCREEN

(1) SIGNAL SYSTEM

Adjust 576 50i

2.R DRIVE XXXX

OK:Store i:Exit

(3) SETTING VALUE (DATA)(2) SETTING ITEM

(2) SETTING ITEM NAME

Setting item name are displayed. The setting item numbers to be displayed are listed below.

Setting mode Setting items Settings

1.ADJUST 1.SC ADJ. Adjust

2.R DRIVE Adjust

3.G DRIVE Adjust

4.B DRIVE Adjust

5.CUTOFF R Fixed [Do not adjust]

6.CUTOFF G Fixed [Do not adjust]

7.CUTOFF B Fixed [Do not adjust]

8.COLOUR Fixed [Do not adjust]

9.HUE Fixed [Do not adjust]

10.CONT. Fixed [Do not adjust]

11.BRIGHT2 Fixed [Do not adjust]

12.SHARP Fixed [Do not adjust]

13.CORING Fixed [Do not adjust]

(3) SETTING VALUE (DATA)

The SETTING VALUE is displayed.

(No.YA604<Rev.001>)1-17

4.6 INITIAL SETTING VALUES IN THE SERVICE MODE

• Perform fine-tuning based on the "initial values" using the remote control when in the Service mode.

• The "initial values" serve only as an indication rough standard and therefore the values with which optimal display can be achieved may be different from the default values.

• Never change the values of the items ( ) that are not described in ADJUSTMENT PROCEDURE or in the below table as they are fixed values.

Item name

1.SC ADJ. 0 - 63 19

2.R DRIVE 0 - 1024 512

3.G DRIVE 0 - 1024 491

4.B DRIVE 0 - 1024 512

5.CUTOFF R -1024 - 1023 0

6.CUTOFF G -1024 - 1023 0

7.CUTOFF B -1024 - 1023 0

Variable

range

Setting value

Item name

8.COLOUR 0 - 256 132 145 98 98

9.HUE -64 - 64 -2 -4 -2 -5

10.CONTRAST 0 - 256 140 140 140 140

11.BRIGHT-2 -1024 - 1023 -3 -11 -3 -11

Item name

8.COLOUR 0 - 256 127 140 130

9.HUE -64 - 64 -3 -4 -4

10.CONTRAST 0 - 256 135 140 118

11.BRIGHT-2 -1024 - 1023 -15 -3 -23

Item name

12.SHARP 0 - 63 32 32 37 32 32

13.CORING 0 - 63 5 5 5 0 2

Item name

12.SHARP 0 - 63 32 32

13.CORING 0 - 63 2 0

Variable

range

Variable

range

Variable

range

Variable

range

PAL (EXT) PAL (RF) SECAM (EXT) SECAM (RF)

Setting value

NTSC_M / NTSC4.43

CONPOSITE_50Hz

S-VIDEO_50Hz

RGB 576i TEXT TWIN

PAL (RF) / SECAM

Setting value

RGB

(RF)

Component /

HDMI

Setting value

CONPOSITE_60Hz

S-VIDEO_60Hz

NTSC_RF RGB 480i

Item name

12.SHARP 0 - 63 35 35 35 35 37

13.CORING 0 - 63 2 2 2 2 2

Item name

12.SHARP 0 - 63 37 37 37 37 37

13.CORING 0 - 63 2 2 2 2 2

1-18 (No.YA604<Rev.001>)

Variable

range

Variable

range

Component 480i Component 576i Component 480p Component 576p

Component 720p60 /

Component 1080i60

Component

1080p50

Setting value

Component

1080p60

Component 1080i50 / Component 1080p50

Component 720p50

Component 1080i50

Component 1080i60 /

Component 1080p60

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