Jvc KW-AVX748-JW, KW-AVX746-UT, KW-AVX746-A, KW-AVX740-J, KW-AVX740-EE Service Manual

SERVICE MANUAL

DVD RECEIVER WITH MONITOR

MA493<Rev.002>20115SERVICE MANUAL

KW-ADV794J, KW-AVX640E, KW-AVX640J,

KW-AVX646EU, KW-AVX646U, KW-AVX648UF,

KW-AVX740E, KW-AVX740EE, KW-AVX740J,

KW-AVX746A, KW-AVX746EU, KW-AVX746U,

KW-AVX746UT, KW-AVX748JW

KW-ADV794/KW-AVX740/

KW-AVX746/KW-AVX748

KW-ADV794J/KW-AVX640J/

For

KW-AVX740J/KW-AVX748JW

KW-AVX740/KW-AVX640/
KW-AVX746/KW-AVX646/

COPYRIGHT © 2011 Victor Company of Japan, Limited

Lead free solder used in the board (material : Sn-Ag-Cu, melting point : 219 Centigrade)
Lead free solder used in the board (material : Sn-Cu, melting point : 230 Centigrade)

KW-AVX740E,EE/KW-AVX640E/

KW-AVX746EU/KW-AVX646EU

For KW-ADV794/

KW-AVX648

For

For

For

KW-ADV794J/

KW-AVX740J/

KW-AVX640J

TABLE OF CONTENTS

1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

2 SPECIFIC SERVICE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9

3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9

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

5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19

COPYRIGHT © 2011 Victor Company of Japan, Limited

No.MA493<Rev.002>

2011/5

SPECIFICATION

KW-ADV794J/KW-AVX748JW/KW-AVX740J/KW-AVX640J

AMPLIFIER

Power Output 20 W RMS × 4 Channels at 4 Ω and
Signal-to-Noise Ratio 80 dBA (reference: 1 W into 4 Ω)
Load Impedance 4 Ω (4 Ω to 8 Ω allowance)
Equalizer Control Range Level ±12 dB
Audio Output Level
FRONT OUT, REAR OUT, SUBWOOFER OUT
Video Output (composite)
VIDEO OUT

Other Terminals Input

FM/AM TUNER

Frequency Range FM with channel interval set to 200 kHz 87.9 MHz to 107.9 MHz

FM Tuner Usable Sensitivity 9.3 dBf (0.8 µV/75 Ω)

AM Tuner Sensitivity/Selectivity 20 µV/40 dB

DVD/CD

Signal Detection System Non-contact optical pickup (semiconductor laser)
Frequency Response DVD, fs=48 kHz/96 kHz 16 Hz to 22 000 Hz

Dynamic Range 93 dB
Signal-to-Noise Ratio 95 dB
Wow and Flutter Less than measurable limit

USB

USB Standards USB 2.0 Full Speed
Data Transfer Rate

Compatible Device Mass storage class
Compatible File System FAT 32/16/12
Max. Current DC 5 V 1A

BLUETOOTH (Only for KW-ADV794/KW-AVX748/KW-AVX740)

Version Bluetooth 2.0 certified
Output Power +4 dBm Max. (Power class 2)
Service Area Within 10 m (10.9 yd)
Profile

MONITOR

Screen Size 6.1 inch wide liquid crystal display
Number of Pixel
Drive Method TFT (Thin Film Transistor) active matrix format
Color System NTSC/PAL
Aspect Ratio 16:9 (wide)

GENERAL

Power Requirement Operating Voltage DC 14.4 V (11 V to 16 V allowance)
Grounding System Negative ground
Allowable Storage Temperature -10°C to +60°C (14°F to 140°F)
Allowable Operating Temperature 0°C to +40°C (32°F to 104°F)
Dimensions (W × H × D) Installation Size (approx.) 182 mm × 111 mm × 160 mm (7-3/16” × 4-3/8” × 6-5/16”)

Mass (approx.) 2.3 kg (5.1 lbs) (including the Trim plate and Sleeve)

*1 Only for KW-ADV794/KW-AVX748/KW-AVX740

*2 Only for KW-ADV794/KW-AVX740/KW-AVX640.
Design and specifications are subject to change without notice.

If a kit is necessary for your car, consult your telephone directory for the nearest car audio speciality shop.

Line-Out Level/Impedance 4 V/20 kΩ load (full scale)
Output Impedance 1 kΩ
Color System

Video-Out Level/Impedance 1 Vp-p/75Ω

Others Expansion port*2, OE REMOTE, RGB input

AM with channel interval set to 10 kHz 530 kHz to 1 700 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 40 dB

VCD/CD 16 Hz to 20 000 Hz

Full Speed Maximum 12 Mbps
Low Speed Maximum 1.5 Mbps

HFP (Hands-Free Profile) 1.5
OPP (Object Push Profile) 1.1
A2DP (Advanced Audio Distribution Profile) 1.2
AVRCP (Audio/Video Remote Control Profile) 1.3
PBAP (Phone Book Access Profile) 1.0

1 152 000 pixels : 800 (horizontal) × 3 (RGB) × 480 (vertical)

Panel Size (approx.) 188 mm × 117 mm × 10 mm (7-7/16” × 4-5/8” × 7/16”)

≤ 1% THD+N

PAL/NTSC

LINE IN, VIDEO IN, CAMERA IN, USB input, MIC IN*1, AUX, Antenna input

with channel interval set to 50 kHz 87.5 MHz to 108.0 MHz

with channel interval set to 9 kHz 531 kHz to 1 611 kHz

1-2 (No.MA493<Rev.002>)

KW-AVX740E/KW-AVX640E/KW-AVX746EU/KW-AVX646EU

AMPLIFIER

Maximum Power Output Front/Rear 50 W per channel
Continuous Power Output (RMS) Front/Rear 20 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 Level ±12 dB
Signal-to-Noise Ratio 70 dB
Audio Output Level
FRONT OUT, REAR OUT,
SUBWOOFER OUT
Video Output (composite)
VIDEO OUT
Other Terminals Input

FM/AM TUNER

Frequency Range FM 87.5 MHz to 108.0 MHz

FM Tuner Usable Sensitivity 9.3 dBf (0.8 µV/75 Ω)

MW Tuner Sensitivity/Selectivity 20 µV/40 dB
LW Tuner Sensitivity 50 µV

DVD/CD

Signal Detection System Non-contact optical pickup (semiconductor laser)
Frequency Response DVD, fs=48 kHz/96 kHz 16 Hz to 22 000 Hz

Dynamic Range 93 dB
Signal-to-Noise Ratio 95 dB
Wow and Flutter Less than measurable limit

USB

USB Standards USB 2.0 Full Speed
Data Transfer Rate Full Speed Maximum 12 Mbps

Compatible Device Mass storage class
Compatible File System FAT 32/16/12
Max. Current DC 5 V 1A

BLUETOOTH (Only for KW-AVX740A/KW-AVX746)

Version Bluetooth 2.0 certified
Output Power +4 dBm Max. (Power class 2)
Service Area Within 10 m
Profile

MONITOR

Screen Size 6.1 inch wide liquid crystal display
Number of Pixel

Drive Method TFT (Thin Film Transistor) active matrix format
Color System PAL/NTSC
Aspect Ratio 16:9 (wide)

GENERAL

Power Requirement Operating Voltage DC 14.4 V (11 V to 16 V allowance)
Grounding System Negative ground
Allowable Storage Temperature -10°C to +60°C
Allowable Operating Temperature 0°C to +40°C
Dimensions (W × H × D) Installation Size (approx.) 182 mm × 111 mm × 160 mm

Mass (approx.) 2.3 kg (including the Trim plate and Sleeve)

Line-Out Level/Impedance
Output Impedance

Color System PAL/NTSC
Video-Out Level/Impedance

Others OE REMOTE, RGB input

AM (MW) 531 kHz to 1 611 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 40 dB

VCD/CD 16 Hz to 20 000 Hz

Low Speed Maximum 1.5 Mbps

HFP (Hands-Free Profile) 1.5
OPP (Object Push Profile) 1.1
A2DP (Advanced Audio Distribution Profile) 1.2
AVRCP (Audio/Video Remote Control Profile) 1.3
PBAP (Phone Book Access Profile) 1.0

1 152 000 pixels : 800 (horizontal) × 3 (RGB) × 480 (vertical)

Panel Size (approx.) 188 mm × 117 mm × 10 mm

4 V/20 kΩ load (full scale)

1 kΩ

1 Vp-p/75 Ω

LINE IN, VIDEO IN, CAMERA IN, USB input, MIC IN*, AUX, Aerial input

(LW) 153 kHz to 279 kHz

* Only for KW-AVX740,KW-AVX746

Design and specifications are subject to change without notice.

(No.MA493<Rev.002>)1-3

KW-AVX740EE

AMPLIFIER

Maximum Power Output Front/Rear 50 W per channel
Continuous Power Output (RMS) Front/Rear 20 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 Level ±12 dB
Signal-to-Noise Ratio 70 dB
Audio Output Level
FRONT OUT, REAR OUT,
SUBWOOFER OUT
Video Output (composite)
VIDEO OUT
Other Terminals Input

FM/AM TUNER

Frequency Range

FM Tuner Usable Sensitivity 9.3 dBf (0.8 µV/75 Ω)

MW Tuner Sensitivity/Selectivity 20 µV/40 dB
LW Tuner Sensitivity 50 µV

DVD/CD

Signal Detection System Non-contact optical pickup (semiconductor laser)
Frequency Response DVD, fs=48 kHz/96 kHz 16 Hz to 22 000 Hz

Dynamic Range 93 dB
Signal-to-Noise Ratio 95 dB
Wow and Flutter Less than measurable limit

USB

USB Standards USB 2.0 Full Speed
Data Transfer Rate Full Speed Maximum 12 Mbps

Compatible Device Mass storage class
Compatible File System FAT 32/16/12
Max. Current DC 5 V 1A

BLUETOOTH

Version Bluetooth 2.0 certified
Output Power +4 dBm Max. (Power class 2)
Service Area Within 10 m
Profile

MONITOR

Screen Size 6.1 inch wide liquid crystal display
Number of Pixel
Drive Method TFT (Thin Film Transistor) active matrix format
Color System PAL/NTSC
Aspect Ratio 16:9 (wide)

GENERAL

Power Requirement Operating Voltage DC 14.4 V (11 V to 16 V allowance)
Grounding System Negative ground
Allowable Storage Temperature -10°C to +60°C
Allowable Operating Temperature 0°C to +40°C
Dimensions (W × H × D) Installation Size (approx.) 182 mm × 111 mm × 160 mm

Mass (approx.) 2.3 kg (including the Trim plate and Sleeve)

Design and specifications are subject to change without notice.

Line-Out Level/Impedance
Output Impedance

Color System PAL/NTSC
Video-Out Level/Impedance

Others OE REMOTE, RGB input

FM

AM (MW) 531 kHz to 1 611 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 40 dB

VCD/CD 16 Hz to 20 000 Hz

Low Speed Maximum 1.5 Mbps

HFP (Hands-Free Profile) 1.5
OPP (Object Push Profile) 1.1
A2DP (Advanced Audio Distribution Profile) 1.2
AVRCP (Audio/Video Remote Control Profile) 1.3
PBAP (Phone Book Access Profile) 1.0

1 152 000 pixels : 800 (horizontal) × 3 (RGB) × 480 (vertical)

Panel Size (approx.) 188 mm × 117 mm × 10 mm

4 V/20 kΩ load (full scale)

1 kΩ

1 Vp-p/75 Ω

LINE IN, VIDEO IN, CAMERA IN, USB input, MIC IN, AUX, Aerial input

FM1, FM2 87.5 MHz to 108.0 MHz

FM3 65.00 MHz to 74.00 MHz

(LW) 153 kHz to 279 kHz

1-4 (No.MA493<Rev.002>)

KW-AVX746A/KW-AVX746U,UT/KW-AVX646U,KW-AVX648UF

AMPLIFIER

Maximum Power Output Front/Rear 50 W per channel
Continuous Power Output (RMS) Front/Rear 20 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 Level ±12 dB
Signal-to-Noise Ratio 70 dB
Audio Output Level
FRONT OUT, REAR OUT,
SUBWOOFER OUT
Video Output (composite)
VIDEO OUT
Other Terminals Input

FM/AM TUNER

Frequency Range FM 87.5 MHz to 108.0 MHz

FM Tuner Usable Sensitivity 9.3 dBf (0.8 µV/75 Ω)

AM Tuner Sensitivity/Selectivity 20 µV/40 dB

DVD/CD

Signal Detection System Non-contact optical pickup (semiconductor laser)
Frequency Response DVD, fs=48 kHz/96 kHz 16 Hz to 22 000 Hz

Dynamic Range 93 dB
Signal-to-Noise Ratio 95 dB
Wow and Flutter Less than measurable limit

USB

USB Standards USB 2.0 Full Speed
Data Transfer Rate Full Speed Maximum 12 Mbps

Compatible Device Mass storage class
Compatible File System FAT 32/16/12
Max. Current DC 5 V 1A

BLUETOOTH (Only for KW-AVX746)

Version Bluetooth 2.0 certified
Output Power +4 dBm Max. (Power class 2)
Service Area Within 10 m
Profile

MONITOR

Screen Size 6.1 inch wide liquid crystal display
Number of Pixel

Drive Method TFT (Thin Film Transistor) active matrix format
Color System PAL/NTSC
Aspect Ratio 16:9 (wide)

GENERAL

Power Requirement Operating Voltage DC 14.4 V (11 V to 16 V allowance)
Grounding System Negative ground
Allowable Storage Temperature -10°C to +60°C
Allowable Operating Temperature 0°C to +40°C
Dimensions (W × H × D)

Mass (approx.) 2.0 kg

Line-Out Level/Impedance
Output Impedance

Color System PAL/NTSC
Video-Out Level/Impedance

Others OE REMOTE, RGB input

AM 531 kHz to 1 611 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 40 dB

VCD/CD 16 Hz to 20 000 Hz

Low Speed Maximum 1.5 Mbps

HFP (Hands-Free Profile) 1.5
OPP (Object Push Profile) 1.1
A2DP (Advanced Audio Distribution Profile) 1.2
AVRCP (Audio/Video Remote Control Profile) 1.3
PBAP (Phone Book Access Profile) 1.0

1 152 000 pixels : 800 (horizontal) × 3 (RGB) × 480 (vertical)

Installation Size (approx.)

Panel Size (approx.) 188 mm × 117 mm × 10 mm

4 V/20 kΩ load (full scale)

1 kΩ

1 Vp-p/75 Ω

LINE IN, VIDEO IN, CAMERA IN, USB input, MIC IN*, AUX, Aerial input

182 mm × 111 mm × 160 mm

180 mm × 100 mm × 160 mm (KW-AVX648)

* Only for KW-AVX746

Design and specifications are subject to change without notice.

(No.MA493<Rev.002>)1-5

SECTION 1

PRECAUTION

1.1 Safety Precautions

(1) This design of this product contains special hardware and

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. Services should be per­formed by qualified personnel only.

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

not be made. Any design alterations of the product should
not be made. Any design alterations or additions will void
the manufacturers warranty and will further relieve the
manufacture 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 the Service Manual. The use of a substitute
replacement which does not have the same safety charac­teristics as the recommended replacement parts shown in
the Parts List of Service Manual may create shock, fire, or
other hazards.

(4) The leads in the products are routed and dressed with ties,

clamps, tubings, barriers and the like to be separated from
live parts, high temperature parts, moving parts and/or
sharp edges for the prevention of electric shock and fire
hazard. When service is required, the original lead routing
and dress should be observed, and it should be confirmed
that they have been returned to normal, after reassem­bling.

(5) Leakage shock hazard testing

After reassembling the product, always perform an isola­tion check on the exposed metal parts of the product (an­tenna terminals, knobs, metal cabinet, screw heads,
headphone jack, control shafts, etc.) to be sure the product
is safe to operate without danger of electrical shock.Do not
use a line isolation transformer during this check.

• Plug the AC line cord directly into the AC outlet. Using a
"Leakage Current Tester", measure the leakage current
from each exposed metal parts of the cabinet, particular­ly any exposed metal part having a return path to the
chassis, to a known good earth ground. Any leakage cur­rent must not exceed 0.5mA AC (r.m.s.).

• Alternate check method
Plug the AC line cord directly into the AC outlet. Use an
AC voltmeter having, 1,000Ω per volt or more sensitivity
in the following manner. Connect a 1,500Ω 10W resistor
paralleled by a 0.15µF AC-type capacitor between an ex­posed metal part and a known good earth ground.
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. Voltage measured any must
not exceed 0.75 V AC (r.m.s.). This corresponds to 0.5
mA AC (r.m.s.).

AC VOLTMETER
(Having 1000
ohms/volts,
or more sensitivity)

0.15 F AC TYPE

Place this
probe on

1500 10W

Good earth ground

1.2 Warning

(1) This equipment has been designed and manufactured to

meet international safety standards.

(2) It is the legal responsibility of the repairer to ensure that

these safety standards are maintained.

(3) Repairs must be made in accordance with the relevant

safety standards.

(4) It is essential that safety critical components are replaced

by approved parts.

(5) If mains voltage selector is provided, check setting for local

voltage.

1.3 Caution

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.

1.4 Critical parts for safety

In regard with component parts appearing on the silk-screen
printed side (parts side) of the PWB diagrams, the parts that are
printed over with black such as the resistor ( ), diode ( )
and ICP ( ) or identified by the " " mark nearby are critical
for safety. When replacing them, be sure to use the parts of the
same type and rating as specified by the manufacturer.
(This regulation dose not Except the J and C version)

each exposed
metal part.

1-6 (No.MA493<Rev.002>)

1.5 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.

1.5.1 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

1M

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.

1.6 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.

1.7 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 card wire is disconnected from the connector on the pickup unit.
(If the card 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 card wire.

Solder short part

(No.MA493<Rev.002>)1-7