JVC KD-LHX555 Service Manual

SERVICE MANUAL

CD/SD RECEIVER

MA15920053

KD-LHX555

Area suffix

UT ------------------------- Taiwan UH ----------------------- Thailand UN ---------------------- Indonesia U --------------------- Other Areas

DISP

TABLE OF CONTENTS

1 PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

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

3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23

5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34

No.MA159

2005/3

SPECIFICATION

AUDIO AMPLIFIER SECTION

Maximum Power Output Front 52 W per channel

Rear 52 W per channel

Continuous Power Output (RMS) Front 19 W per channel into 4 Ω, 40 Hz to 20 000 Hz at no more

than 0.8% total harmonic distortion.

Rear 19 W per channel into 4 Ω, 40 Hz to 20 000 Hz at no more

than 0.8% total harmonic distortion.

Load Impedance 4 Ω (4 Ω to 8 Ω allowance)

Equalizer Control Range Frequencies 60 Hz, 150 Hz, 400 Hz, 1 kHz, 2.4 kHz, 6 kHz, 12 kHz

Level ±10 dB

Frequency Response 40 Hz to 20 000 Hz

Signal-to-Noise Ratio 70 dB

Line-Out Level/Impedance 5.0 V/20 kΩ load (full scale) Output Impedance 1 kΩ Subwoofer-Out Level/Impedance 5.0 V/20 kΩ load (full scale)

Other Terminals LINE IN, CD changer

TUNER SECTION

Frequency Range FM 87.5 MHz to 108.0 MHz

AM 531 kHz to 1 602 kHz

FM Tuner Usable Sensitivity 11.3 dBf (1.0 µV/75 Ω)

50 dB Quieting Sensitivity 16.3 dBf (1.8 µV/75 Ω)

Alternate Channel Selectivity (400 kHz) 65 dB

Frequency Response 40 Hz to 15 000 Hz

Stereo Separation 35 dB

Capture Ratio 1.5 dB

AM Tuner Sensitivity 20 µV

Selectivity 65 dB

CD/SD PLAYER SECTION

Type Compact disc player

Signal Detection System Non-contact optical pickup (semiconductor laser)

Number of Channels 2 channels (stereo)

Frequency Response 5 Hz to 20 000 Hz

Dynamic Range 98 dB

Signal-to-Noise Ratio 102 dB

Wow and Flutter Less than measurable limit

MP3 (MPEG Audio Layer 3) Max. Bit Rate 320 kbps

WMA (Windows Media Audio) Max. Bit Rate 192 kbps

Playable SD Card Format Fat 12/16

Storage Up to 512 MB

Playable Audio Format for SD Card MP3/WMA

GENERAL

Power Requirement Operating Voltage DC 14.4 V (11 V to 16 V allowance)

Grounding System Negative ground

Allowable Operating Temperature 0°C to +40°C Dimensions (W × H × D) Installation Size (approx.) 182 mm × 52 mm × 159 mm

Panel Size (approx.) 188 mm × 58 mm × 13 mm

Mass (approx.) 1.9 kg (excluding accessories)

Design and specifications are subject to change without notice.

1-2 (No.MA159)

1.1 Safety Precautions

SECTION 1

PRECAUTIONS

Burrs formed during molding may be left over on some parts of the chassis. Therefore, pay attention to such burrs in the case of preforming repair of this system.

Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check.

(No.MA159)1-3

1.2 Preventing static electricity

Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laser diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.

1.2.1 Grounding to prevent damage by static electricity

Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as CD players. Be careful to use proper grounding in the area where repairs are being performed.

(1) Ground the workbench

Ground the workbench by laying conductive material (such as a conductive sheet) or an iron plate over it before placing the traverse unit (optical pickup) on it.

(2) Ground yourself

Use an anti-static wrist strap to release any static electricity built up in your body.

(caption) Anti-static wrist strap

Conductive material (conductive sheet) or iron plate

(3) Handling the optical pickup

• In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement optical pickup are shorted. After replacement, return the shorted parts to their original condition. (Refer to the text.)

• Do not use a tester to check the condition of the laser diode in the optical pickup. The tester's internal power source can easily destroy the laser diode.

1.3 Handling the traverse unit (optical pickup)

(1) Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit. (2) Cut off the shorted part of the flexible cable using nippers, etc. after replacing the optical pickup. For specific details, refer to the

replacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long a

time when attaching it to the connector. (3) Handle the flexible cable carefully as it may break when subjected to strong force. (4) It is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it.

1.4 Attention when traverse unit is decomposed

*Please refer to "Disassembly method" in the text for the CD pickup unit.

• Apply solder to the short land before the flexible wire is disconnected from the connector on the CD pickup unit. (If the flexible wire is disconnected without applying solder, the CD pickup may be destroyed by static electricity.)

• In the assembly, be sure to remove solder from the short land after connecting the flexible wire.

Short sections

Flexible wire

1-4 (No.MA159)

CN601

Mechanism control board

1.5 Important for laser products

1.CLASS 1 LASER PRODUCT

2.DANGER : Invisible laser radiation when open and inter

lock failed or defeated. Avoid direct exposure to beam.

3.CAUTION : There are no serviceable parts inside the

Laser Unit. Do not disassemble the Laser Unit. Replace

the complete Laser Unit if it malfunctions.

4.CAUTION : The CD,MD and DVD player uses invisible

laser radiation and is equipped with safety switches which

prevent emission of radiation when the drawer is open and

the safety interlocks have failed or are defeated. It is

dangerous to defeat the safety switches.

5.CAUTION : If safety switches malfunction, the laser is able

to function.

6.CAUTION : Use of controls, adjustments or performance of

procedures other than those specified here in may result in

hazardous radiation exposure.

Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check.

REPRODUCTION AND POSITION OF LABELS

WARNING LABEL

CAUTION : Visible and Invisible

CLASS 1 LASER PRODUCT

laser radiation when open and interlock failed or defeated. AVOID DIRECT EXPOSURE TO BEAM. (e)

ADVARSEL : Synlig og usynlig laserstråling når maskinen er åben eller interlocken fejeler. Undgå direkte eksponering til stråling. (d)

VARNING : Synlig och osynling laserstrålning när den öppnas och spärren är urkopplad. Betrakta ej strålen. (s)

VARO : Avattaessa ja suojalukitus ohitettuna tai viallisena olet alttiina näkyvälle ja näkymättömälle lasersäteilylle. Vältä säteen kohdistumista suoraan itseesi. (f)

(No.MA159)1-5

SECTION 2

SPECIFIC SERVICE INSTRUCTIONS

This service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.

1-6 (No.MA159)

SECTION 3

DISASSEMBLY

3.1 Main body section

3.1.1 Removing the front panel assembly (See Fig.1)

(1) Push the detach button in the lower right part of the front

panel assembly.

(2) Remove the front panel assembly.

3.1.2 Removing the heat sink (See Fig.2)

Reference:

Remove the front panel assembly as required.

(1) From the left side of the main body, remove the two screws

A and three screws B attaching the heat sink.

(2) Remove the heat sink from the main body.

Front panel assembly

Detach button

Fig.1

AAB

Heat sink

Fig.2

(No.MA159)1-7

3.1.3 Removing the top chassis assembly (See Figs.3 to 6)

• Prior to performing the following procedures, remove the heat

sink.

Reference:

Remove the front panel assembly as required. (1) From the bottom side of the main body, remove the two

screws C attaching the top chassis assembly to the bottom chassis assembly. (See Fig.3.)

(2) From the both and rear sides of the main body, remove the

four screws D attaching the top chassis assembly to the bottom chassis assembly. (See Figs.4 to 6.)

(3) Remove the two screws E attaching the IC heat sink. (See

Fig.5.)

(4) Lift the top chassis assembly in the direction of the arrow,

disconnect the connector CN503 trol board from the connector CN721 (See Figs.4 to 6.)

(5) Take out the top chassis assembly from the bottom chassis

assembly.

on the mechanism con-

on the main board.

Bottom chassis assembly

Top chassis assembly

Fig.3

Top chassis assembly

CN503

Main board

Bottom chassis assembly

Mechanism control board

Top chassis assembly

Mechanism control board

CN721

Fig.4

IC heat sink

Bottom chassis assembly

1-8 (No.MA159)

Top chassis assembly

Bottom chassis assembly

Fig.5

Rear bracket

Fig.6

3.1.4 Removing the front chassis assembly

(See Figs.7 and 8)

• Prior to performing the following procedure, remove the front

panel assembly, heat sink and top chassis assembly. (1) From the both sides of the top chassis assembly, remove

the two screws F attaching the front chassis assembly.

(2) Remove the front chassis assembly from the top chassis

assembly.

Top chassis assembly

Front chassis assembly

Fig.7

Top chassis assembly

Front chassis assembly

3.1.5 Removing the CD mechanism assembly

(See Fig.9)

• Prior to performing the following procedures, remove the front

panel assembly, heat sink and top chassis assembly.

Reference:

Remove the front chassis assembly as required.

(1) From the inside of the top chassis assembly, remove the

three screws G attaching the CD mechanism assembly.

(2) Release the mecha heat sink from the joints a on the mech-

anism control board and remove the heat sink from the main body.

(3) Take out the CD mechanism assembly from the top chas-

sis.

Top chassis

Fig.8

Mechanism control board

Mecha heat sink

G G

CD mechanism assembly

Fig.9

(No.MA159)1-9

3.1.6 Removing the main board (See Figs.10 and 11)

• Prior to performing the following procedures, remove the front

panel assembly, heat sink and top chassis assembly. (1) From the rear side of the bottom chassis assembly, remove

the two screws H attaching the rear bracket to the bottom chassis assembly. (See Fig.10.)

(2) From the top side of the bottom chassis assembly, remove

the two screws J attaching the main board to the bottom chassis assembly. (See Fig.11.)

(3) Release the stopper of the connector CN701

board in an upward direction, disconnect the card wire from the connector CN701

(4) Disconnect the wire from the connector of the front door

mechanism assembly. (See Fig.11.)

(5) Disconnect the wire from the connector CN991

board. (See Fig.11.)

Reference:

After connecting the wires, fix the wires with the wire holders.

(6) Take out the main board from the bottom chassis assem-

bly.

. (See Fig.11.)

on the main

Rear bracket

Front door mechanism assembly

Connector

Wire holders

Bottom chassis assembly

Fig.10

Card wire

CN701

Stopper

Bottom chassis assembly

Main board

Wires

CN991

Fig.11

1-10 (No.MA159)

3.1.7 Removing the rear bracket

(See Fig.12)

• Prior to performing the following procedures, remove the front

panel assembly, heat sink, top chassis assembly and main board. (1) From the rear side of the main board, remove the wires

from the rear bracket in the direction of the arrow.

(2) Remove the screw K and four screws L attaching the rear

bracket to the main board.

Reference:

After attaching the rear bracket to the main board, pass the wires through the wire holder and insert them into the slots of the rear bracket.

3.1.8 Removing the front door mechanism assembly

(See Fig.13)

• Prior to performing the following procedures, remove the front

panel assembly, heat sink, top chassis assembly and main board. (1) From the top side of the bottom chassis assembly, remove

the screw M attaching the FPC guide to the bottom chassis.

(2) Remove the five screws N attaching the front door mecha-

nism assembly to the bottom chassis.

Reference:

When attaching the screws M and N, apply a locking agent them.

(3) Take out the front door mechanism assembly from the bot-

tom chassis.

Rear bracket

Bottom chassis

Wires

Main board

Wire holder

Slots

Rear bracket

LL L

Fig.12

Front door mechanism assembly

FPC guide

Fig.13

(No.MA159)1-11

3.1.9 Removing the switch board (See Figs.14 to 16)

• Prior to performing the following procedures, remove the front

panel assembly. (1) From the rear side of the front panel assembly, remove the

four screws P attaching the rear cover to the front panel assembly. (See Fig.14.)

(2) Release the twelve joints b of the front panel assembly and

remove the rear cover. (See Fig.15.)

(3) Take out the switch board from the front panel assembly.

(See Fig.16.)

Rear cover

Fig.14

b b

Front panel assembly

Rear cover

Fig.15

Switch board

Fig.16

1-12 (No.MA159)

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