JVC KD-G162, KD-G161, KD-G126, KD-G125, KD-G124 Service Manual

SERVICE MANUAL

CD RECEIVER

KD-G120,KD-G120R,KD-G123, KD-G124,KD-G125,KD-G126, KD-G161,KD-G162

	KD-G120	KD-G120R		KD-G120,KD-G120R
				Area suffix
			J -------------	Northern America
	KD-G123	KD-G124		KD-G123,KG-G124
				Area suffix
			UI ----------------------------	India
	KD-G125	KD-G126		KD-G125,KD-G126
	KD-G126	KD-G125		Area suffix
			UT	------------------------- Taiwan
			UH	---------------------- Thailand
	KD-G161	KD-G162	UN	--------------------- Indonesia
			U	Other Areas
	KD-G161	KD-G162
				KD-G161,KD-G162
				Area suffix
			E -------------	Southern Europe
			EX	------------ Northern Europe
			EY	------------- Eastern Europe
			EU	------------------------- Turkey

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

TABLE OF CONTENTS

1 PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6 2 SPECIFIC SERVICE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9 3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10 4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13 5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

COPYRIGHT © 2005 Victor Company of Japan, Limited

No.MA233

2005/12

SPECIFICATION

KD-G120R/KD-G120

AUDIO AMPLIFIER SECTION

Power Output		17 W RMS × 4 Channels at 4 Ω			and [< or =] 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)
Tone Control Range	Bass	±10 dB at 100 Hz
	Treble	±10 dB at 10 kHz
Frequency Response		40 Hz to 20 000 Hz
Line-Out Level/Impedance		2.0 V/20 kΩ load (full scale)
Output Impedance		1 kΩ
Subwoofer-Out Level/Impedance		2.0 V/20 kΩ load (full scale)
	TUNER SECTION
Frequency Range	FM	87.5 MHz to 107.9 MHz (with channel interval set to 100 kHz or 200 kHz)
		87.5 MHz to 108.0 MHz (with channel interval set to 50 kHz)
	AM	530 kHz to 1 710 kHz (with channel interval set to 10 kHz)
		531 kHz to 1 602 kHz (with channel interval set to 9 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	35 dB
	CD 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		96 dB
Signal-to-Noise Ratio		98 dB
Wow and Flutter		Less than measurable limit
		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 (32°F to 104°F)
Dimensions (W × H × D)	Installation Size (approx.)	182 mm ×	52 mm ×	150 mm (7-3/16" ×		2-1/16" ×	5-15/16")
	Panel Size (approx.)	188 mm ×	58 mm ×	11 mm (7-7/16" ×		2-5/16" ×	7/16")
Mass (approx.)		1.2 kg (2.6 lbs) (excluding accessories)

Design and specifications are subject to change without notice.

1-2 (No.MA233)

KD-G124/KD-G123

AUDIO AMPLIFIER SECTION

Maximum Power Output	Front	50 W per channel
	Rear	50 W per channel
Continuous Power Output	Front	19 W per channel into 4 Ω			, 40 Hz to 20 000 Hz at no more than 0.8% total har-
(RMS)		monic distortion.
	Rear	19 W per channel into 4 Ω			, 40 Hz to 20 000 Hz at no more than 0.8% total har-
		monic distortion.
Load Impedance		4 Ω (4 Ω to 8 Ω allowance)
Tone Control Range	Bass	±10 dB at 100 Hz
	Treble	±10 dB at 10 kHz
Frequency Response		40 Hz to 20 000 Hz
Signal to Noise Ratio		70 dB
Line-Out Level/Impedance		2.0 V/20 kΩ load (full scale)
Output Impedance		1 kΩ
Subwoofer-Out Level/Impedance		2.0 V/20 kΩ load (full scale)
	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	35 dB
	CD 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		96 dB
Signal-to-Noise Ratio		98 dB
Wow and Flutter		Wow and Flutter: Less than measurable limit
		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 ×	150 mm
	Panel Size (approx.)	188 mm ×	58 mm ×	11 mm
Mass (approx.)		1.2 kg (excluding accessories)

Design and specifications are subject to change without notice.

(No.MA233)1-3

KD-G126/KD-G125

AUDIO AMPLIFIER SECTION

Maximum Power Output	Front	50 W per channel
	Rear	50 W per channel
Continuous Power Output	Front	19 W per channel into 4 Ω			, 40 Hz to 20 000 Hz at no more than 0.8% total har-
(RMS)		monic distortion.
	Rear	19 W per channel into 4 Ω			, 40 Hz to 20 000 Hz at no more than 0.8% total har-
		monic distortion.
Load Impedance		4 Ω (4 Ω to 8 Ω allowance)
Tone Control Range	Bass	±10 dB at 100 Hz
	Treble	±10 dB at 10 kHz
Frequency Response		40 Hz to 20 000 Hz
Signal to Noise Ratio		70 dB
Line-Out Level/Impedance		2.0 V/20 kΩ load (full scale)
Output Impedance		1 kΩ
Subwoofer-Out Level/Impedance		2.0 V/20 kΩ load (full scale)
	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	35 dB
	CD 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		96 dB
Signal-to-Noise Ratio		98 dB
Wow and Flutter		Less than measurable limit
		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 ×	150 mm
	Panel Size (approx.)	188 mm ×	58 mm ×	11 mm
Mass (approx.)		1.2 kg (excluding accessories)

Design and specifications are subject to change without notice.

1-4 (No.MA233)

KD-G162/KD-G161

AUDIO AMPLIFIER SECTION

Maximum Power Output	Front	45 W per channel
	Rear	45 W per channel
Continuous Power Output	Front	17 W per channel into 4 Ω			, 40 Hz to 20 000 Hz at no more than 0.8% total har-
(RMS)		monic distortion.
	Rear	17 W per channel into 4 Ω			, 40 Hz to 20 000 Hz at no more than 0.8% total har-
		monic distortion.
Load Impedance		4 Ω (4 Ω to 8 Ω allowance)
Tone Control Range	Bass	±10 dB at 100 Hz
	Treble	±10 dB at 10 kHz
Frequency Response		40 Hz to 20 000 Hz
Signal-to-Noise Ratio		70 dB
Line-Out Level/Impedance		2.0 V/20 kΩ load (full scale)
Output Impedance		1 kΩ
	TUNER SECTION
Frequency Range	FM	87.5 MHz to 108.0 MHz
	AM	(MW) 522 kHz to 1 620 kHz
		(LW) 144 kHz to 279 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	30 dB
	Capture Ratio	1.5 dB
MW Tuner	Sensitivity	20 µV
	Selectivity	35 dB
LW Tuner	Sensitivity	50 µV
	CD 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		96 dB
Signal-to-Noise Ratio		98 dB
Wow and Flutter		Less than measurable limit
		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 ×	150 mm
	Panel Size (approx.)	188 mm ×	58 mm ×	11 mm
Mass (approx.)		1.2 kg (excluding accessories)

Design and specifications are subject to change without notice.

(No.MA233)1-5

SECTION 1

PRECAUTIONS

1.1Safety 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.

1-6 (No.MA233)

1.2Preventing 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.

1.2.1Grounding 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

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.

1.3Handling 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.

1.4Attention 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.

						Pickup
Wires						Push switch

Base board

	Frame	CD mechanism
		assembly
	Flexible wire
		Pickup
	Connector

(No.MA233)1-7

1.5Important 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

CLASS 1

LASER PRODUCT

CAUTION : Visible and Invisible 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)

1-8 (No.MA233)

SECTION 2

SPECIFIC SERVICE INSTRUCTIONS

2.1CD mechanism

For the CD mechanism, please refer mechanism manual TN2007-1001 (No. MY003).

(No.MA233)1-9

SECTION 3

DISASSEMBLY

3.1Main body section

3.1.1Removing 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 bottom cover (See Fig.2)

(1)Turn the main body up side down.

(2)Insert a screwdriver under the joints to release the two

joints a on the left side, two joints b on the right side and	Joint a
joint c on the back side of the main body, then remove the
bottom cover from the main body.
Note:
When releasing the joints using a screwdriver, do not damage
the main board.

Joint a

3.1.3Removing the front chassis assembly (See Fig.3)

•Remove the front panel assembly and bottom cover.

(1)Remove the two screws A on the both sides of the main body.

(2)Release the two joints d and two joints e on the both sides of the main body, then remove the front chassis assembly toward the front.

Front panel assembly

Detach button

Fig.1

Bottom cover

Joint b

Joint b

Joint c

Fig.2

Joint d

Joint e

A

Joint d Joint e

Front chassis assembly

Fig.3

1-10 (No.MA233)

3.1.4Removing the side panel (See Fig.4)

Reference:

Remove the front panel assembly as required.

(1)Remove the screw B and two screws C attaching the side panel on the left side of the main body.

(2)Remove the side panel from the main body.

3.1.5 Removing the rear bracket (See Fig.5)

•Remove the bottom cover.

(1)Remove the three screws D, three screws E and two screws F attaching the rear bracket on the back side of the main body.

(2)Remove the rear bracket.

3.1.6 Removing the main board (See Figs.5 and 6)

•Remove the front panel assembly, bottom cover and side panel.

Reference:

Remove the front chassis assembly as required.

(1)Remove the three screws D attaching the rear bracket on the back side of the main body. (See Fig.5.)

(2)Remove the two screws G attaching the main board. (See Fig.6.)

(3)Disconnect the connector CN501 on the main board from the main body and take out the main board with the rear bracket. (See Fig.6.)

Reference:

Remove the rear bracket from the main body as required. (See "3.1.5 Removing the rear bracket".)

C B C

Side panel

Fig.4

Rear bracket

E E F

F

D	D
	Fig.5
	Main board
	CN501
G	G

Rear bracket

Fig.6

(No.MA233)1-11

3.1.7 Removing the CD mechanism assembly (See Fig. 7)

•Remove the front panel assembly, bottom cover, side panel, rear bracket and main board.

Reference:

Remove the front chassis assembly as required.

(1)Remove the three screws H attaching the CD mechanism assembly on the top chassis.

(2)Take out the CD mechanism assembly.

3.1.8Removing the switch board (See Figs.8 to 10)

•Remove the front panel assembly.

(1)Remove the four screws J on the back side of the front panel assembly. (See Fig.8.)

(2)Release the joints f and remove the rear cover. (See Fig.9.)

(3)Release the joint g and take out the switch board from the front panel assembly. (See Fig.10.)

H

CD mechanism assembly

Top chassis

H

Fig.7

J

J J

Fig.8

Joints f

Rear cover

Joints f

Joints f

Joints f

Fig.9

Front panel assembly

Switch board

Joint g

Fig.10

1-12 (No.MA233)

SECTION 4 ADJUSTMENT

4.1Adjustment method

Test instruments required for adjustment

(1)Digital oscilloscope (100MHz)

(2)Electric voltmeter

(3)Digital tester

(4)Tracking offset meter

(5)Test Disc JVC :CTS-1000

(6)Extension cable for check EXTSH002-22P × 1

Standard volume position

Balance and Bass &Treble volume : lndication"0" Loudness : OFF

Standard measuring conditions

Power supply voltage	DC14.4V(10.5 to 16V)
Load impedance	20KΩ (2 Speakers connection)
Output Level	Line out 2.0V (Vol. MAX)

Dummy load

Exclusive dummy load should be used for AM,and FM. For FM dummy load,there is a loss of 6dB between SSG output and antenna input.The loss of 6dB need not be considered since direct reading of figures are applied in this working standard.

How to connect the extension cable for adjusting

Caution:

Be sure to attach the heat sink and rear bracket onto the power amplifier IC and regulator IC respectively, before supply the power. If voltage is applied without attaching these parts, the power amplifier IC and regulator IC will be destroyed by heat.

CAUTION :

Be sure to attach the heat sink and rear bracket onto the power amplifier and regulator respectively, before supply the power.

If voltage is applied without attaching those parts, the power amplifier IC and regulator IC will be destroyed by heat.

Extension cable

Heat sink	EXTSH002-22P
	Rear bracket

(No.MA233)1-13

SECTION 5

TROUBLESHOOTING

5.1Trouble shooting (For KD-G120, KD-G120R, KD-G123, KD-G124,KD-G125 and KD-G126)

5.1.1 Feed section

Is 4V present at both sides of the feed motor?

NO

Is the voltage output at pin 4 and pin 5 of IC541?

NO

Is the voltage input at pin 28 of IC541?

NO

Is the voltage output at pin 21 and pin 22 of IC561?

NO

Is the power supply present at pin 4, pin 50, pin 60 and pin 72 of IC561?

NO

Check the connections of CD8V power supply.

5.1.2 Focus section

YES

YES

YES

YES

YES

Check the feed motor.

Check the connections between the feed motor and IC541.

Is the power supply present at pin 3, pin 12 and pin 21 of IC541?

NO

Check the connections of CD8V power supply.

Check the connections between IC541 and IC561.

Check IC561.

When the lens is moving:

4V YES

Does the S-search waveform appear at IC541 pins 8 and 9?

NO

Is the voltage input at pin YES 15 of IC541?

		NO
			YES
	Is the voltage output at
	pin 28 of IC561?
		NO

Check the pickup and its connections.

Is the power supply present at pin 3, pin 12 and pin 21 of IC541?

NO

Check the connections of CD8V power supply.

Check the connections between IC541 and IC561.

YES

Check IC541.

YES

Check IC541.

	Is the power supply		YES
	present at pin 4, pin 50,				Check IC561.
	pin 60 and pin 72 of IC561?
		NO
	Check the connections
	of CD8V power supply.

1-14 (No.MA233)

5.1.3 Spindle section
		YES			YES
	Is the disk rotated?			Does the RF signal			Is the RF waveform
				appear at RF TP?			at TP RF distorted?

		NO
			YES
	Is the voltage output at
	pin 6 and pin 7 of IC541?

NO

Is the voltage input at pin YES 17 of IC541?

NO

Is the voltage output at pin YES 24 and pin 25 of IC561?

NO

	Is the power supply		YES
	present at pin 4, pin 50,
	pin 60 and pin 72 of IC561?
		NO
	Check the connections
	of CD8V power supply.
5.1.4 Tracking section

NO NO

Check the spindle motor

and its wiring. Check the circuits in the vicinity of IC501

or the pickup.

	Is the power supply		YES
					Check IC541.
	present at pin 3, pin 12
	and pin 21 of IC541?
		NO
	Check the connections
	of CD8V power supply.
	Check the connections
	between IC541 and
	IC561.
	Check IC561.

When the disc is rotated at first:

Approx. 1.2V

Is the tracking error signal output at TE TP?

NO

Check the circuits in IC501 or the vicinity of IC501.

NO

Replace IC501 or repair the malfunction connection point

YES

Check IC561.

	YES
			Check the pickup and
			its connections.

YES

Proceed to the Tracking section

(No.MA233)1-15

5.1.5 Signal processing section

Is the sound output from	YES
both channels (L, R)?		Normal

NO

No sound from either channel.

NO

Compare the L-ch and R-ch to locate the defective point.

Is the audio signal

YES

YES

(including sampling

YES

Is the audio signal output

Is 9V present at pin 26

output components)

at pin 22 and pin 25 of

of IC301?

output to pins 1 and 7 of

IC301 during playback?

IC151 during playback?

NO

NO

Check IC151 and its

Check IC301 and its

peripheral circuits.

peripheral circuits.

NO

Is 9V present at pin 10

YES

Check the connections

YES

of IC901?

between pin 26 of IC301

Check the power

and pin 10 of IC901.

amplifier IC321.

NO

Check IC901 and its

peripheral circuits.

1-16 (No.MA233)

5.2Trouble shooting (For KD-G161 and KD-G162)

5.2.1 Feed section

Is 4V present at both sides of the feed motor?

NO

Is the voltage output at pin 4 and pin 5 of IC501?

NO

Is the voltage input at pin 28 of IC501?

NO

Is the voltage output at pin 7 of IC521?

NO

YES

YES

YES

YES

Check the feed motor.
Check the connections
between the feed motor
and IC501.
Is the power supply
		YES		Check IC501.
present at pin 3, pin 12
and pin 21 of IC501?
	NO
Check the connections
of CD8V power supply.
Check the connections
between IC501 and
IC521.

Is the power supply

present at pin 16, pin 37, YES pin 49, pin 53, pin 56

and pin 72 of IC521?

NO

Check the connections of CD8V power supply.

5.2.2 Focus section

When the lens is moving:

4V YES

Does the S-search waveform appear at IC501 pins 8 and 9?

NO

Is the voltage input at pin YES 15 of IC501?

		NO
			YES
	Is the voltage output at
	pin 13 of IC521?
		NO

Check IC521.

Check the pickup and its connections.

	Is the power supply		YES
					Check IC501.
	present at pin 3, pin 12
	and pin 21 of IC501?
		NO
	Check the connections
	of CD8V power supply.
	Check the connections
	between IC501 and
	IC521.

Is the power supply

present at pin 16, pin 37, YES

Check IC521.

pin 49, pin 53, pin 56 and pin 72 of IC521?

NO

Check the connections of CD8V power supply.

(No.MA233)1-17

5.2.3 Spindle section
		YES				YES
	Is the disk rotated?			Does the RF signal appear				Is the RF waveform at
				at pin 39 of IC521?				pin 39 of IC521 distorted?

	NO
		YES
	Is the voltage output at
	pin 6 and pin 7 of IC501?

NO

Is the voltage input at pin YES 17 of IC501?

NO

Is the voltage output at YES pin 5 of IC521?

NO

NO NO

Check the spindle motor and its wiring. Check the circuits in

the vicinity of IC521 or the pickup.

	Is the power supply		YES
					Check IC501.
	present at pin 3, pin 12
	and pin 21 of IC501?
		NO
	Check the connections
	of CD8V power supply.
	Check the connections
	between IC501 and
	IC521.

Is the power supply

present at pin 16, pin 37, YES

Check IC521.

pin 49, pin 53, pin 56 and pin 72 of IC521?

NO

Check the connections of CD8V power supply.

5.2.4 Tracking section

When the disc is rotated at first:

Approx. 1.2V YES Replace IC521 or repair

the malfunction

connection point

Is the tracking error signal output at pin 26 of IC521?

NO

Check the pickup and its connections.

YES

Proceed to the Tracking section

1-18 (No.MA233)

5.2.5 Signal processing section

Is the sound output from	YES
both channels (L, R)?		Normal

NO

No sound from either channel.

NO

Compare the L-ch and R-ch to locate the defective point.

Is the audio signal

Is the audio signal output

YES

YES

(including sampling

YES

Is 9V present at pin 32

at pin 14,pin 15, pin 18

of IC171?

output components)

and pin 19 of IC171 during

output to pins 1 and 7 of

playback?

IC581 during playback?

NO

NO

Check IC581 and its

Check IC171 and its

peripheral circuits.

peripheral circuits.

NO

Is 9V present at pin 13

YES

Check the connections

YES

of IC901?

between pin 32 of IC171

Check the power

and pin 13 of IC901.

amplifier IC301.

NO

Check IC901 and its

peripheral circuits.

(No.MA233)1-19