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

SERVICE MANUAL

DVD RECEIVER WITH MONITOR

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

For

KW-ADV794/KW-AVX740/

KW-AVX746/KW-AVX748

	For	For
		KW-AVX740E,EE/KW-AVX640E/
	KW-ADV794J/KW-AVX640J/
		KW-AVX746EU/KW-AVX646EU
	KW-AVX740J/KW-AVX748JW

	For
For KW-ADV794/	KW-ADV794J/

KW-AVX740/KW-AVX640/ KW-AVX740J/

KW-AVX746/KW-AVX646/ KW-AVX640J

KW-AVX648

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)

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 ≤ 1% THD+N
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		Line-Out Level/Impedance			4 V/20 kΩ load (full scale)
FRONT OUT, REAR OUT, SUBWOOFER OUT
		Output Impedance			1 kΩ
Video Output (composite)		Color System			PAL/NTSC
VIDEO OUT
		Video-Out Level/Impedance			1 Vp-p/75Ω
Other Terminals		Input			LINE IN, VIDEO IN, CAMERA IN, USB input, MIC IN*1, AUX, Antenna input
		Others			Expansion port*2, OE REMOTE, RGB input
FM/AM TUNER
Frequency Range		FM			with channel interval set to 200 kHz	87.9 MHz to 107.9 MHz
					with channel interval set to 50 kHz		87.5 MHz to 108.0 MHz
		AM			with channel interval set to 10 kHz		530 kHz to 1 700 kHz
					with channel interval set to 9 kHz		531 kHz to 1 611 kHz
FM Tuner		Usable Sensitivity			9.3 dBf (0.8 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			40 dB
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
		VCD/CD			16 Hz to 20 000 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
		Low Speed			Maximum 1.5 Mbps
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		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
MONITOR
Screen Size		6.1 inch wide liquid crystal display
Number of Pixel		1 152 000 pixels : 800 (horizontal) × 3 (RGB) × 480 (vertical)
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”)
		Panel Size (approx.)			188 mm × 117 mm × 10 mm (7-7/16” × 4-5/8” × 7/16”)
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.

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	Line-Out Level/Impedance			4 V/20 kΩ load (full scale)
FRONT OUT, REAR OUT,
	Output Impedance			1 kΩ
SUBWOOFER OUT
Video Output (composite)	Color System			PAL/NTSC
VIDEO OUT	Video-Out Level/Impedance			1 Vp-p/75 Ω
Other Terminals	Input			LINE IN, VIDEO IN, CAMERA IN, USB input, MIC IN*, AUX, Aerial input
	Others			OE REMOTE, RGB input
FM/AM TUNER
Frequency Range	FM			87.5 MHz to 108.0 MHz
	AM			(MW) 531 kHz to 1 611 kHz
				(LW) 153 kHz to 279 kHz
FM Tuner	Usable Sensitivity			9.3 dBf (0.8 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			40 dB
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
	VCD/CD			16 Hz to 20 000 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
	Low Speed			Maximum 1.5 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	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
MONITOR
Screen Size	6.1 inch wide liquid crystal display
Number of Pixel	1 152 000 pixels : 800 (horizontal) × 3 (RGB) × 480 (vertical)
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
	Panel Size (approx.)			188 mm × 117 mm × 10 mm
Mass (approx.)	2.3 kg (including the Trim plate and Sleeve)

* 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	Line-Out Level/Impedance			4 V/20 kΩ load (full scale)
FRONT OUT, REAR OUT,
	Output Impedance			1 kΩ
SUBWOOFER OUT
Video Output (composite)	Color System			PAL/NTSC
VIDEO OUT	Video-Out Level/Impedance			1 Vp-p/75 Ω
Other Terminals	Input			LINE IN, VIDEO IN, CAMERA IN, USB input, MIC IN, AUX, Aerial input
	Others			OE REMOTE, RGB input
FM/AM TUNER
Frequency Range	FM			FM1, FM2	87.5 MHz to 108.0 MHz
				FM3	65.00 MHz to 74.00 MHz
	AM			(MW) 531 kHz to 1 611 kHz
				(LW) 153 kHz to 279 kHz
FM Tuner	Usable Sensitivity			9.3 dBf (0.8 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			40 dB
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
	VCD/CD			16 Hz to 20 000 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
	Low Speed			Maximum 1.5 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	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
MONITOR
Screen Size	6.1 inch wide liquid crystal display
Number of Pixel	1 152 000 pixels : 800 (horizontal) × 3 (RGB) × 480 (vertical)
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
	Panel Size (approx.)			188 mm × 117 mm × 10 mm
Mass (approx.)	2.3 kg (including the Trim plate and Sleeve)

Design and specifications are subject to change without notice.

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	Line-Out Level/Impedance			4 V/20 kΩ load (full scale)
FRONT OUT, REAR OUT,
	Output Impedance			1 kΩ
SUBWOOFER OUT
Video Output (composite)	Color System			PAL/NTSC
VIDEO OUT	Video-Out Level/Impedance			1 Vp-p/75 Ω
Other Terminals	Input			LINE IN, VIDEO IN, CAMERA IN, USB input, MIC IN*, AUX, Aerial input
	Others			OE REMOTE, RGB input
FM/AM TUNER
Frequency Range	FM			87.5 MHz to 108.0 MHz
	AM			531 kHz to 1 611 kHz
FM Tuner	Usable Sensitivity			9.3 dBf (0.8 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			40 dB
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
	VCD/CD			16 Hz to 20 000 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
	Low Speed			Maximum 1.5 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	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
MONITOR
Screen Size	6.1 inch wide liquid crystal display
Number of Pixel	1 152 000 pixels : 800 (horizontal) × 3 (RGB) × 480 (vertical)
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
				180 mm × 100 mm × 160 mm (KW-AVX648)
	Panel Size (approx.)			188 mm × 117 mm × 10 mm
Mass (approx.)	2.0 kg

* Only for KW-AVX746

Design and specifications are subject to change without notice.

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

SECTION 1 PRECAUTION

1.1Safety 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

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

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	each exposed
	metal part.

Good earth ground

1.2Warning

(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.

1.3Caution

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.

1.4Critical 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)

1.5Preventing 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.

1.5.1Grounding 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.

1.6Handling 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.

1.7Attention 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