JVC LT-32SH6/A, LT-37SH6/A Service Manual

SERVICE MANUAL

LCD FLAT TELEVISION

YA38220067

LT-32SH6/A, LT-37SH6

[LT-37SH6/A]

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

2 SPECIFIC SERVICE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5

3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16

TABLE OF CONTENTS

No.YA382

2006/7

SPECIFICATION

Item

Dimensions (W × H × D) 80.8 cm × 55.9 cm × 10.8 cm (TV only)

80.8 cm × 62.8 cm × 30.9 cm (Included Stand)

Mass 20.0 kg (Included Stand) 27.2 kg (Included Stand)

Power Input AC 240V, 50Hz

Power Consumption 168W (Stand-by : 1W) 217W (Stand-by : 1W)

TV RF System Analogue

Color System PAL

Stereo System A2/NICAM system, Digital (MPEG2)

Receiving Frequency

Intermediate Frequency

Colour Sub Carrier Frequency

Teletext System FLOF (Fastext), WST(World Standard system)

LCD Panel 32V wide aspect (16 : 9) 37V wide aspect (16 : 9)

Screen Size Diagonal : 80 cm (H: 69.7 cm × V: 39.2 cm) Diagonal : 94.9 cm (H: 82.6 cm × V: 46.7 cm) Display Pixels Horizontal : 1366 pixels × Vertical : 768 pixels (W-XGA)

Audio Power Output 10W + 10W

Speaker 6.6cm round type × 2 6.6cm round type × 4 Aerial terminal (VHF/UHF) 75 Ω unbalanced, coaxial

Video / Audio Input-1/2

Video / Audio Output [DTV ONLY]

PC (RGB) Input

Digital Audio Output Opticl Connector × 1 Headphone 3.5mm mini jack × 1 (Stereo) Remote Control Unit RM-C1896 (AA/R6 battery × 2)

AC Adapter DA-E056705025

Component Video

Analogue

SECAM

[Input-2]

750p / 1125i

625p / 625i

S-Video

[Input-1]

CCIR (B/G)

Digital

DVB-T

48.25 MHz - 863.25 MHz

Digital

174 MHz - 858 MHz

VIF

38.9MHz (B/G)

SIF

33.4MHz (5.5MHz :B/G)

PAL

4.43MHz

4.40625MHz / 4.25MHz

NTSC

4.43MHz

RCA pin jack × 3 Y : 1V (p-p) (Sync signal: ±0.35V(p-p), 3-value sync.), 75 Ω Pb/Pr : ±0.35V(p-p), 75 Ω Y : 1V (p-p), Positive (Negative sync provided), 75 Ω Pb/Pr : 0.7V(p-p), 75 Ω Mini-DIN 4 pin connector × 1 Y: 1V (p-p), Positive (Negative sync provided), 75 Ω C: 0.286V (p-p) (Burst signal), 75 Ω

Video

1V (p-p), Positive (Negative sync provided), 75 Ω, RCA pin jack × 1

Audio

500mV (rms), High impedance, RCA pin jack × 4

Video

1V (p-p), Positive (Negative sync provided), 75 Ω, RCA pin jack × 1

Audio

500mV (rms), Low impedance, RCA pin jack × 2

Video

D-sub 15 pin × 1 R/G/B : 0.7 V (p-p), 75Ω

HD / VD : 1 V (p-p) to 5 V (p-p), high impedance < Available signal >

VGA : 640 pixels × 480 pixels (Horizontal : 31.5 kHz / Vertical : 60 Hz) XGA : 1024 pixels × 768 pixels (Horizontal : 48.4 kHz / Vertical : 60 Hz)

Audio

500mV (rms), Low impedance, RCA pin jack × 2

LT-32SH6 LT-37SH6

Contents

92.6 cm × 63.2 cm × 10.9 cm (TV only)

92.6 cm × 70.1 cm × 32.5 cm (Included Stand)

NOTE : Design & specifications are subject to change without notice.

1-2 (No.YA382)

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) Do not check high voltage by drawing an arc. Use a high

voltage meter or a high voltage probe with a VTVM. Discharge the picture tube before attempting meter connection, by connecting a clip lead to the ground frame

and connecting the other end of the lead through a 10kΩ

2W resistor to the anode button.

(7) 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 1000

Ω per volt or more

sensitivity in the following manner. Connect a 1500

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

PLACE THIS PROBE

1500 10W

GOOD EARTH GROUND

ON EACH EXPOSED ME TAL PAR T

Ω

(No.YA382)1-3

1.2 INSTALLATION

1.2.1 HEAT DISSIPATION

If the heat dissipation vent behind this unit is blocked, cooling efficiency may deteriorate and temperature inside the unit will rise. 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.

1.2.2 INSTALLATION REQUIREMENTS

Ensure that the minimal distance is maintained, as specified below, between the unit with and the surrounding walls. 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.

Distance recommendations

Avoid improper installation and never position the unit where good ventilation is impossible. When installing this TV, distance recommendations must be maintained between the set and the wall, as well as inside a tightly enclosed area or

150 mm

200 mm 200 mm

150 mm

50 mm

piece of furniture. Keep to the minimum distance guidelines shown for safe operation.

1.3 PRECAUTIONS

(1) The picture brightness may become uneven on the entire screen according to the environmental temperature. Be sure to use

your monitor set in a specified temperature range for proper display presentation.

(2) Avoid disturbing the heat dissipation from the vent holes provided in the rear, on the top and at the sides. Failure to do so may

result in damaged electronics inside due to the accumulated heat within the unit.

(3) Be sure to install the unit in a well-ventilated place. Also make sure that the ambient temperature is kept in the range of 0 to 35°C.

(4) Avoid operation or storage in high temperature and humidity that exceed the specified limit. Otherwise, the display presentation

may be deteriorated.

(5) This monitor may display a blurred picture when exposed to an extreme environmental conditions. This phenomenon is due to

an intrinsic characteristic of the Liquid Crystal Display (LCD). This is not the failure.

(6) This monitor display uses a Cold Cathode Tube as a backlighting device. The brilliance of this tube (and the monitor display)

may be degraded by time.

1.4 CAUTIONS FOR TRANSPORTATION

The goods may be damaged during transportation caused by poor handling such as throwing, toppling, dropping, etc, giving an excess force against the LCD device. This may happen even if the packing is rigid and secured. To avoid such adverse situations, give a proper instruction to the freighter for secured handling. The LCD panel uses a glass plate, which is very fragile against an external force. Take utmost care to avoid vibration or shock to the panel.

1-4 (No.YA382)

SECTION 2

SPECIFIC SERVICE INSTRUCTIONS

2.1 ABOUT LIQUID CRYSTAL DISPLAY

2.1.1 STRUCTURE OF LIQUID CRYSTAL PANEL

The Liquid Crystal Display used for this unit is of a TFT (Thin Film Transistor) type panel. The structure of this panel is that a TFT array-formed substrate and the stripe pixel matrix type color filter substrate are pressed together with a liquid crystal filled in between these materials.

2.1.2 LONG-TERM AFTERIMAGE ON THE LCD

A minute amount of ionic material could be mingled into a liquid crystal substrate in the manufacturing process. By applying the electricity to the panel the ionic material may be migrated towards one part of the electrodes, causing a long-term afterimage to be displayed. In practice, when a still image is displayed for a long time, the afterimage may be developed and persisted. To cure this problem, turn off the unit and then turn on again and arrange displaying an appropriate still image on the portion where the afterimage is being superimposed.

2.1.3 RESPONSE SPEED OF THE LCD

The LCD is slower than the CRT in terms of the display refresh rate, causing a fast moving picture may be displayed blurred. This is not fault but caused by an intrinsic characteristic of the LCD.

2.1.4 VIEWING ANGLE OF THE LCD

This LCD uses a wide-angle liquid crystal panel, featuring a low rate of the brightness inversion. When viewed from a far outer angle, the screen may be displayed with hue variation. Again, this is not fault but caused by an intrinsic characteristic of the LCD.

2.1.5 PIXEL DEFICIENCY OF THE LCD

The liquid crystal panel is manufactured with precise engineering procedure. However, there is a possibility of yielding a little amount of defective pixels in part on the panel. This is unavoidable feature even if the latest technology is being used for manufacturing the LCD module.

2.2 IMPORTANT NOTICE WHEN REPLACING COMPONENT PARTS

2.2.1 REPLACING THE LCD MODULE

(1) The LCD panel is fragile against the static charge. Be sure to take an appropriate grounding using a grounding-strap etc. when

to replace the LCD panel. (2) The LCD is made of glass, which is fragile against the mechanical shock. Use utmost care when handling the LCD panel. (3) When replacing the panel, first place the panel on the base chassis and then make sure that there is no gap in between the panel

and the chassis. Fix the panel with fixing screws. Turn the unit on with an all-black signal being put in and check if the brightness

is even on the entire screen. If the brightness is not even in some part, slacken the fixing screw nearby until the brightness

becomes even with other parts. (4) A tightening torque for the fixing screws must be set to 0.294Nm or the less. Applying the torque larger than this limit may result

in the damage on the LCD panel. (5) Connecting or disconnecting the plugs with the set is being powered may cause the malfunction of the set. Makes sure that the

AC power plug is disconnected from the power source when attempting the replacement work.

2.2.2 REPLACING THE FUSE

Be sure to use the rated fuse. After replacing the fuse, confirm that the insulator is stuck on the shielding surface for secure insulation.

(No.YA382)1-5

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.

• When removing each board, remove the connectors as required. Taking notes of the connecting points (connector numbers) makes service procedure manageable.

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

3.2 DISASSEMBLY PROCEDURE [LT-32SH6/A]

3.2.1 REMOVING THE STAND (Fig.1)

(1) Remove the 2 screws [A], then remove the STAND COVER. (2) Remove the 4 screws [B], then remove the STAND.

3.2.2 REMOVING THE REAR COVER (Fig.1)

• Remove the STAND. (1) Remove the JACK COVER (L/R). (2) Remove the 7 screws [C], the 4 screws [D], and the 1 screw [E]. (3) Remove the REAR COVER.

3.2.3 REMOVING THE POWER CORD HOLDER AND SD

CARD BASE (Fig.1)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 2 screws [F], then remove the POWER CORD

HOLDER.

(2) Remove the 1 screw [G], then remove the SD CARD BASE.

3.2.6 REMOVING THE DVB PWB (Fig.1)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 3 screws [N], then remove the TUNER BASE. (2) Remove the 1 screw [P] and the 2 screws [Q], then remove

the DVB PWB SHIELD.

(3) Remove the 5 screws [R], then remove the DVB PWB.

3.2.7 REMOVING THE KEY PWB (Fig.1)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 2 screws [S], then remove the KEY PWB. (2) Remove the 2 screws [T], then remove the CONTROL ASS'Y.

3.2.4 REMOVING THE MAIN PWB (Fig.1)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 4 screws [H], then remove the MAIN PWB SHIELD. (2) Remove the 3 screws [J], then remove the TERMINAL BASE. (3) Remove the 7 screws [K], then remove the MAIN PWB.

3.2.5 REMOVING THE POWER PWB (Fig.1)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 5 screws [L], then remove the FAN BRACKET. (2) Remove the 6 screws [M], then remove the POWER PWB.

1-6 (No.YA382)

JACK COVER

REAR COVER

MAIN PWB

TERMINAL BASE

JACK COVER

SHIELD

POWER

CORD

HOLDER

FAN BRACKET

MALAR

POWER PWB

MALAR

DVB PWB

SHIELD

DVB PWB

STAND COVER

STAND

TUNER

BASE

MAIN PWB

KEY

PWB

CONTROL

ASS'Y

SD CARD BASE

FRONT

Fig.1

(No.YA382)1-7

3.2.8 REMOVING THE SPEAKER (Fig.2)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 7 screws [A], then remove the SPEAKER BOX. (2) Remove the 4 screws [B], then remove the SPEAKER (L/R). (3) Remove the 4 screws [C], then remove the DUCT(L/R).

NOTE:

Since the speaker is attached in a certain direction, attach the speaker in the same correct direction as it has been attached.

3.2.9 REMOVING THE LCD PANEL UNIT (Fig.2)

• Remove the STAND.

• Remove the REAR COVER.

• Remove the POWER CORD HOLDER.

• Remove the MAIN PWB.

• Remove the POWER PWB.

• Remove the DVB PWB. (1) Remove the 10 screws [D] and 1 screw [E], then remove

the MAIN BASE.

(2) Remove the 7 screws [F], then remove the LCD PANEL

UNIT whit the TOP FRAME and BOTTOM FRAME.

(3) Remove the 4 screws [G], then remove the TOP FRAME

and BOTTOM FRAME from the LCD PANEL UNIT.

3.2.10 REMOVING THE IR PWB (Fig.2)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 2 screws [H], then remove the IR PWB.

3.2.11 REMOVING THE LED LENS (Fig.2)

• Remove the STAND.

• Remove the REAR COVER.

• Remove the IR PWB. (1) Remove the 2 screws [J], then remove the LED LENS.

1-8 (No.YA382)

TOP FRAME

LCD PANEL UNIT

BOTTOM

FRAME

FRONT PANEL

MAIN BASE

SPEAKER BOX

DUCT

FRONT

IR PWB

SPEAKER

LED LENS

SPEAKER

FRONT

Fig.2

(No.YA382)1-9

3.3 DISASSEMBLY PROCEDURE [LT-37SH6/A]

3.3.1 REMOVING THE STAND (Fig.3)

(1) Remove the 1 screw [A], then remove the STAND COVER. (2) Remove the 4 screws [B], then remove the STAND.

3.3.2 REMOVING THE REAR COVER (Fig.3)

• Remove the STAND. (1) Remove the JACK COVER (L/R). (2) Remove the 8 screws [C], the 3 screws [D], the 2 screws [E] and

the 2 screws [F].

(3) Remove the REAR COVER.

3.3.3 REMOVING THE POWER CORD HOLDER AND SD

CARD BASE (Fig.3)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 2 screws [G], then remove the POWER

CORD HOLDER.

(2) Remove the 2 screws [H], then remove the SD CARD BASE.

3.3.4 REMOVING THE MAIN PWB (Fig.3)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 6 screws [J], then remove the MAIN PWB SHIELD. (2) Remove the 3 screws [K], then remove the TERMINAL BASE. (3) Remove the 7 screws [L], then remove the MAIN PWB.

3.3.6 REMOVING THE DVB PWB (Fig.3)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 3 screws [P], then remove the TUNER BASE. (2) Remove the 2 screws [Q], then remove the DVB PWB SHIELD. (3) Remove the 5 screws [R], then remove the DVB PWB.

3.3.7 REMOVING THE KEY PWB (Fig.3)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 2 screws [S], then remove the KEY PWB. (2) Remove the 2 screws [T], then remove the CONTROL ASS'Y.

3.3.5 REMOVING THE POWER PWB (Fig.3)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 5 screws [M], then remove the FAN BRACKET. (2) Remove the 6 screws [N], then remove the POWER PWB.

1-10 (No.YA382)

JACK COVER

REAR COVER

MAIN PWB

SHIELD

FAN BRACKET

MALAR

POWER PWB

DVB PWB

SHIELD

STAND COVER

STAND

TUNER BASE

MAIN PWB

TERMINAL BASE

KEY PWB

CONTROL

ASS'Y

POWER

CORD

HOLDER

MALAR

DVB PWB

SD CARD

BASE

FRONT

Fig.3

(No.YA382)1-11

3.3.8 REMOVING THE SPEAKER (Fig.4)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 6 screws [A] and 6 spacers [B], then remove

the SPEAKER (L/R).

NOTE:

Since the speaker is attached in a certain direction, attach the speaker in the same correct direction as it has been attached.

3.3.9 REMOVING THE LCD PANEL UNIT (Fig.4)

• Remove the STAND.

• Remove the REAR COVER.

• Remove the POWER CORD HOLDER.

• Remove the MAIN PWB.

• Remove the POWER PWB.

• Remove the DVB PWB. (1) Remove the 10 screws [C] and 1 screw [D], then remove

the MAIN BASE.

(2) Remove the 2 screws [E], 2 screws [F] and 3 screws [G],

then remove the TOP FRAME.

(3) Remove the 1 screw [H], then remove the SD CARD PWB

BRACKET.

(4) Remove the 3 screws [J] and 2 screws [K], then remove

the BOTTOM FRAME.

(5) Remove the LCD PANEL from the FRONT PANEL.

3.3.10 REMOVING THE IR PWB (Fig.4)

• Remove the STAND.

• Remove the REAR COVER. (1) Remove the 2 screws [L], then remove the IR PWB.

3.3.11 REMOVING THE LED LENS (Fig.4)

• Remove the STAND.

• Remove the REAR COVER.

• Remove the IR PWB. (1) Remove the 2 screws [M], then remove the LED LENS.

1-12 (No.YA382)

MAIN BASE

SD CARD PWB

TOP FRAME

BRACKET

BOTTOM

FRAME

SPEAKER

LCD PANEL UNIT

SPEAKER

IR PWB

FRONT PANEL

LED

LENS

FRONT

Fig.4

(No.YA382)1-13

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.

1-14 (No.YA382)

(4) Then solder leads B and C.

SECTION 4

ADJUSTMENT

This service manual does not describe ADJUSTMENT.

(No.YA382)1-15

SECTION 5

TROUBLESHOOTING

No picture appwear

Check if the Power

Does the LED

light up

Cord has been well

connected to TV?

Replace P807

Picture

shows

MCU (I016) Hangs

End

Reset the

MCU (I016)

Still no Picture

Replace I016

End

LED display is

Is it entering into

power saving mode

Restart PC signal

to ensure H.V. sync

are not absent

amber

End

YES

Is the input voltage

applied to Power

supply unit?

(Cnl #3 #4 is 5V)

YES

The Voltage of

P002 #3 #4 is 5V

YES

The Voltage of I013 #36 is 5V

YES

Replace I013

Replace PSU1

Replace P002A

Check I013

socketis

loosened

The Voltage of I025 #2 is 3.3V

YES

The Voltage of I009 #2 is 3.3V

YES

Replace I025

Replace I009

The Ver. or Hor. sync

does not hold

Are the output of

SVP-EX52

(CLK, H, V, DE)

normal

Are the input

waveforms of

SVP-EX52 normal

Replace I037

(SVP-EX52)

End

Are flex cable

attached firmly

at P003

Tighten two flex

cables at P003

End End

1-16 (No.YA382)

Are flex cable

attached firmly at

the LCD panel

connectors

Replace V901

(LCD panel)

Tighten flex cable

at P003

End

The Voltage of I028 #2 is 2.5V

YES

The Voltage of

I001 #2 is 5V

YES

The Voltage of I004 #2 is 1.8V

YES

The Voltage of I003 #2 is 1.8V

YES

The Voltage of I019 #2 is 3.3V

YES

Replace I037

(SVP-EX52)

Replace I028

Replace I001

Replace I004

Replace I003

Replace I019

End

Victor Company of Japan, Limited Display Category 12, 3-chome, Moriya-cho, Kanagawa-ku, Yokohama-city, Kanagawa-prefecture, 221-8528, Japan

(No.YA382)

Printed in Japan

VPT

SCHEMATIC DIAGRAMS

LCD FLAT TELEVISION

LT-32SH6/A, LT-37SH6

CD-ROM No.SML200607

[LT-37SH6/A]

No.YA382

2006/7

LT-32SH6

, LT-37SH6

STANDARD CIRCUIT DIAGRAM

NOTE ON USING CIRCUIT DIAGRAMS

1.SAFETY

The components identified by the symbol and shading are critical for safety. For continued safety replace safety ciritical components only with manufactures recommended parts.

2.SPECIFIED VOLTAGE AND WAVEFORM VALUES

The voltage and waveform values have been measured under the following conditions.

(1)Input signal : Colour bar signal

(2)Setting positions of each knob/button and variable resistor

(3)Internal resistance of tester

(4)Oscilloscope sweeping time

(5)Voltage values

Since the voltage values of signal circuit vary to some extent according to adjustments, use them as reference values.

: Original setting position when shipped

: DC 20kΩ/V

: H

: V

: Othters

: All DC voltage values

20µs / div

5ms / div

Sweeping time is specified

3.INDICATION OF PARTS SYMBOL [EXAMPLE]

In the PW board

: R1209

R209

Type

No indication

MM PP

MPP

MF TF BP

TAN

(3)Coils

No unit

Others

(4)Power Supply

Respective voltage values are indicated

(5)Test point

: Test point

(6)Connecting method

: Ceramic capacitor : Metalized mylar capacitor

: Polypropylene capacitor : Metalized polypropylene capacitor : Metalized film capacitor : Thin film capacitor : Bipolar electrolytic capacitor : Tantalum capacitor

: [µH]

: As specified

: B1

: 9V

: Connector

: Receptacle

: Only test point display

: Wrapping or soldering

: B2 (12V

: 5V

)

4.INDICATIONS ON THE CIRCUIT DIAGRAM

(1)Resistors

Resistance value

No unit : [Ω]

K M

Rated allowable power No indication : 1/16 [W]

Others : As specified

Type

No indication

OMR

MFR

MPR

UNFR

Composition resistor 1/2 [W] is specified as 1/2S or Comp.

(2)Capacitors

Capacitance value

1 or higher : [pF]

less than 1

Withstand voltage

No indication : DC50[V]

Others : DC withstand voltage [V]

AC indicated

Electrolytic Capacitors

47/50[Example]: Capacitance value [µF]/withstand voltage[V]

: [kΩ]

: [MΩ]

: Carbon resistor

: Oxide metal film resistor

: Metal film resistor

: Metal plate resistor

: Uninflammable resistor

: Fusible resistor

: [µF]

: AC withstand voltage [V]

(7)Ground symbol

: LIVE side ground

: ISOLATED(NEUTRAL) side ground

: EARTH ground

: DIGITAL ground

5.NOTE FOR REPAIRING SERVICE

This model's power circuit is partly different in the GND. The difference of the GND is shown by the LIVE : ( ) side GND and the ISOLATED(NEUTRAL) : ( ) side GND. Therefore, care must be taken for the following points.

(1)Do not touch the LIVE side GND or the LIVE side GND and the ISOLATED(NEUTRAL) side GND simultaneously. if the above caution is not respected, an electric shock may be caused. Therefore, make sure that the power cord is surely removed from the receptacle when, for example, the chassis is pulled out.

(2)Do not short between the LIVE side GND and ISOLATED(NEUTRAL side GND or never measure with a measuring apparatus measure with a measuring apparatus ( oscilloscope, etc.) the LIVE side GND and ISOLATED(NEUTRAL) side GND at the same time. If the above precaution is not respected, a fuse or any parts will be broken.

Since the circuit diagram is a standard one, the circuit and circuit constants may be subject to change for improvement without any notice.

NOTE Due improvement in performance, some part numbers show in the circuit diagram may not agree with those indicated in the part list. When ordering parts, please use the numbers that appear in the Parts List.

)

(No.YA382)2-1

+ 42 hidden pages

JVC LT-32SH6/A, LT-37SH6/A Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual