JVC KDLHX-502 Service manual

SERVICE MANUAL

CD RECEIVER

MA04520044

KD-LHX501,KD-LHX502

Area suffix

E ----------- Continental Europe EX --------------- Central Europe EU -------------------------- Turkey

T/P

FRONT PANEL COLOR

KD-LHX501

SILVER BLACK

KD-LHX502

TABLE OF CONTENTS

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

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

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

4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28

5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-29

No.MA045

2004/4

SPECIFICATION

AUDIO AMPLIFIER SECTION

Maximum Power Output Front 50 W per channel

Rear 50 W per channel

Continuous Power Output (RMS)

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

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

Other Terminals SUBWOOFER OUT

Frequency Range FM 87.5 MHz to 108.0 MHz

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

[MW Tuner] Sensitivity 20 µV

[LW Tuner] Selectivity 50 µV

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

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

Grounding System Negative ground

Allowable Operating Temperature 0ºC to +40ºC

Dimensions (W × H × D) Installation Size 182 mm × 52 mm × 157.5 mm

Mass 1.86 kg (excluding accessories)

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.

Level ±10 dB

Changer control

Steering wheel remote input

TUNER SECTION

AM (MW) 522 kHz to 1 620 kHz

(LW) 144 kHz to 279 kHz

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

Selectivity 65 dB

CD PLAYER SECTION

GENERAL

Panel Size 188 mm × 58 mm × 13 mm

Design and specifications are subject to change without notice.

1-2 (No.MA045)

1.1 Safety Precautions

SECTION 1

PRECAUTION

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.MA045)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 laser products. 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 pickup unit.

• Apply solder to the short land before the flexible wire is disconnected from the connector on the pickup unit. (If the flexible wire is disconnected without applying solder, the 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-circuit point

(Soldering)

Flexible wire

1-4 (No.MA045)

Pickup

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.MA045)1-5

SECTION 2

SPECIFIC SERVICE INSTRUCTIONS

This service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.

1-6 (No.MA045)

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 and remove the front panel assembly.

3.1.2 Removing the heat sink (See Fig.2)

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

A and three screws B attaching the heat sink.

Front panel assembly

Detach button

Fig.1

AAB

Heat sink

Fig.2

(No.MA045)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

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

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

disconnect the connector CN501 trol board from the connector CN721 on the main board. (See Figs.5 and 6.)

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

assembly.

on the mechanism con-

Bottom chassis assembly

Top chassis assembly

Fig.3

Top chassis assembly

Bottom chassis assembly

Mechanism control board

Top chassis assembly

Main board

Bottom chassis assembly

Fig.4

CN501

CN721

Fig.5

Top chassis assembly

1-8 (No.MA045)

Rear bracket

Bottom chassis assembly

Fig.6

3.1.4 Removing the front chassis

(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 E attaching the front chassis.

3.1.5 Removing the mechanism control board

(See Fig.9)

• Prior to performing the following procedures, remove the front

panel assembly, heat sink and top chassis assembly. (1) Disconnect the card wire from the connector CN601

mechanism control board.

(2) Remove the five screws F attaching the mechanism control

board.

(3) Release the joints a and b, remove the mechanism control

board.

on the

Top chassis assembly

Front chassis

Mechanism control board

Front chassis

Fig.7

Top chassis assembly

Fig.8

CN601

Fig.9

(No.MA045)1-9

3.1.6 Removing the CD mechanism assembly (See Fig.10)

• Prior to performing the following procedures, remove the front

panel assembly, heat sink and top chassis assembly.

Reference:

Remove the mechanism control board as required. (1) From the inside of the top chassis assembly, remove the

three screws G attaching the CD mechanism assembly.

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

sis.

3.1.7 Removing the main board (See Figs.11 and 12)

• 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.11.)

(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.12.)

(3) Release the stopper of the connector CN701

board in an upward direction, disconnect the card wire from the connector CN701. (See Fig.12.)

(4) Disconnect the wire from the connector of the gear bracket

unit. (See Fig.12.)

(5) Disconnect the wire from the connector CN991

board. (See Fig.12.)

Reference:

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

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

bly.

on the main

Top chassis

Gear bracket unit

Connector

Wire holder

CD mechanism assembly

Fig.10

Rear bracket

Bottom chassis assembly

Fig.11

Card wire

CN701

Stopper

Bottom chassis assembly

1-10 (No.MA045)

Main board

Wires

CN991

Fig.12

3.1.8 Removing the rear bracket

(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 rear side of the main board, remove the wires

from the rear bracket in the direction of the arrow.

(2) Remove the two screws K and three 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.

Rear bracket

Wire

Main board

Wire holder

Slots

Rear bracket

3.1.9 Removing the gear bracket unit

(See Fig.14)

• 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 gear bracket unit

to the bottom chassis.

Reference:

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

(3) Take out the gear bracket unit from the bottom chassis.

Bottom chassis

L K

FPC guide

Fig.13

Gear bracket unit

Fig.14

(No.MA045)1-11

3.1.10 Removing the front board (See Figs.15 to 17)

• 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 assembly to the front panel assembly. (See Fig.15.)

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

remove the rear cover assembly. (See Fig.16.)

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

(See Fig.17.)

Rear cover assembly

Fig.15

joints c joints c

Rear cover assembly

joints c joints c

Fig.16

Front panel assembly

Front board

Fig.17

1-12 (No.MA045)

3.2 CD Mechanism section

3.2.1 Removing the top cover

(See Figs.1 and 2)

(1) Remove the four screws A on the both side of the body. (2) Lift the front side of the top cover and move the top cover

backward to release the two joints a.

Top cover

Joints a

Fig.1

Fig.2

Top cover

(No.MA045)1-13

3.2.2 Removing the connector board (See Figs.3 to 5)

CAUTION:

Before disconnecting the flexible wire from the pickup, solder the short-circuit point on the pickup. No observance of this instruction may cause damage of the pickup. (1) Remove the screw B fixing the connector board. (2) Solder the short-circuit point on the pickup. (3) Disconnect the flexible wire from the pickup. (4) Move the connector board in the direction of the arrow to

release the two joints b.

(5) Unsolder the wires on the connector board if necessary.

CAUTION:

Unsolder the short-circuit point after reassembling.

Connector board

Flexible wire

Wires

Joints b

Short-circuit point

Fig.3

Short-circuit point

(Soldering)

Pickup

Flexible wire

Frame

Pickup

Fig.4

Connector board

Fig.5

1-14 (No.MA045)

3.2.3 Removing the DET switch

(See Figs.6 and 7)

(1) Extend the two tabs c of the feed sw. holder and pull out

the switch.

(2) Unsolder the DET switch wire if necessary.

DET

switch

Connector

board

Pickup

Fig.6

DET switch

Tab c

DET switch wire

Feed sw. holder

Fig.7

(No.MA045)1-15

3.2.4 Removing the chassis unit

(See Figs.8 and 9)

• Prior to performing the following procedure, remove the top

cover and connector board. (1) Remove the two suspension springs (L) and (R) attaching

the chassis unit to the frame.

CAUTION:

• The shape of the suspension spring (L) and (R) are different. Handle them with care.

• When reassembling, make sure that the three shafts on the underside of the chassis unit are inserted to the dampers certainly.

Suspension spring (R)

Chassis unit

Suspension spring (L)

Frame

Suspension spring (R)

Chassis unit

Shafts

Damper

Suspension spring (L)

Fig.8

Shaft

Dampe

Frame

Fig.9

1-16 (No.MA045)

3.2.5 Removing the clamper assembly (See Figs.10 and 11)

• Prior to performing the following procedure, remove the top

cover. (1) Remove the clamper arm spring. (2) Move the clamper assembly in the direction of the arrow to

release the two joints d.

Clamper arm spring

Joint d

Clamper assembly

Fig.10

Clamper arm spring

Chassis rivet assembly

Joint d

Clamper assembly

Chassis rivet assembly

Joint d

Fig.11

(No.MA045)1-17

3.2.6 Removing the loading / feed motor assembly (See Figs.12 and 13)

• Prior to performing the following procedure, remove the top

cover, connector board and chassis unit. (1) Remove the screw C and move the loading / feed motor as-

sembly in the direction of the arrow to remove it from the chassis rivet assembly.

(2) Disconnect the wire from the loading / feed motor assembly

if necessary.

CAUTION:

When reassembling, connect the wire from the loading / feed motor assembly to the flame as shown in Fig.12.

Loading / feed motor assembly

Fig.12

Loading / feed motor assembly

Fig.13

1-18 (No.MA045)

3.2.7 Removing the pickup unit

(See Figs.14 to 18)

• Prior to performing the following procedure, remove the top

cover, connector board and chassis unit. (1) Remove the screw D and pull out the pu. shaft holder from

the pu. shaft. (2) Remove the screw E attaching the feed sw. holder. (3) Move the part e of the pickup unit upward with the pu. shaft

and the feed sw. holder, then release the joint f of the feed

sw. holder in the direction of the arrow. The joint g of the

pickup unit and the feed rack is released, and the feed sw.

holder comes off. (4) Remove the pu. shaft from the pickup unit. (5) Remove the screw F attaching the feed rack to the pickup

unit.

3.2.8 Reattaching the pickup unit (See Figs.14 to 17)

(1) Reattach the feed rack to the pickup unit using the screw F. (2) Reattach the feed sw. holder to the feed rack while setting

the joint g to the slot of the feed rack and setting the joint f of the feed rack to the switch of the feed sw. holder correctly.

(3) As the feed sw. holder is temporarily attached to the pickup

unit, set to the gear of the joint g and to the bending part of the chassis (joint h) at a time.

CAUTION:

Make sure that the part i on the underside of the feed rack is certainly inserted to the slot j of the change lock

lever. (4) Reattach the feed sw. holder using the screw E. (5) Reattach the pu. shaft to the pickup unit. Reattach the pu.

shaft holder to the pu. shaft using the screw D.

Part e

Joint g

Feed sw. holder

Feed rack

Part i

Slot j

Fig.15

Pu. shaft

Pickup unit

Joint f

Joint h

Fig.16

Feed rack

Pickup unit

Feed sw. holder

Pu. shaft holde

Joint f

Pu. shaft

Pu. shaft holder

Feed sw. holder

Pickup unit

Fig.14

Part e

Joint g

Pickup unit

Feed rack

Fig.17

Pickup unit

Joint g

Joint f

Feed sw. holder

Fig.18

(No.MA045)1-19

3.2.9 Removing the trigger arm

(See Figs.19 and 20)

• Prior to performing the following procedure, remove the top cover, connector board and clamper unit. (1) Turn the trigger arm in the direction of the arrow to release

the joint k and pull out upward.

CAUTION:

When reassembling, insert the part m and n of the trigger arm into the part p and q at the slot of the chassis rivet assembly respectively and join the joint k at a time.

Chassis rivet assembly

Trigger arm

Chassis

rivet

assembly

Joint k

Trigger arm

Fig.19

Part p

Part q

Part m

Part n

3.2.10 Removing the top plate assembly

(See Fig.21)

• Prior to performing the following procedure, remove the top cover, connector board, chassis unit, and clamper assembly. (1) Remove the screw H. (2) Move the top plate assembly in the direction of the arrow to

release the two joints r.

(3) Unsolder the wire marked s if necessary.

Fig.20

Top plate assembly

Joints

Fig.21

1-20 (No.MA045)

3.2.11 Removing the mode sw. / select lock arm (See Figs.22 and 23)

• Prior to performing the following procedure, remove the top

plate assembly. (1) Bring up the mode sw. to release from the link plate (joint t)

and turn in the direction of the arrow to release the joint u. (2) Unsolder the wire of the mode sw. marked s if necessary. (3) Turn the select lock arm in the direction of the arrow to re-

lease the two joints v. (4) The select lock arm spring comes off the select lock arm at

the same time.

Link plate

Joint u

Fig.22

Joint t

Mode sw.

Select lock arm

Top plate

Select lock arm

Link plate

Select lock arm

Fig.23

Top plate

Hook w

Select lock arm spring

Joints v

(No.MA045)1-21

3.2.12 Reassembling the mode sw. / select lock arm (See Figs.24 to 26)

REFERENCE:

Reverse the above removing procedure. (1) Reattach the select lock arm spring to the top plate and set

the shorter end of the select lock arm spring to the hook w on the top plate.

(2) Set the other longer end of the select lock arm spring to the

boss x on the underside of the select lock arm, and join the select lock arm to the slots (joint v). Turn the select lock arm as shown in the figure.

(3) Reattach the mode sw. while setting the part t to the first

peak of the link plate gear, and join the joint u.

CAUTION:

When reattaching the mode sw., check if the points y and z are correctly fitted and if each part operates properly.

Select lock arm spring

Hook w

Joint v

Select lock arm

Boss x

Fig.24

Joint t

Point y

Link plate

Point z

Link plate

Fig.25

Mode sw.

Select lock arm

Joint t

Joint u

Fig.26

1-22 (No.MA045)

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