Kenwood KDC-2031-SA, KDC-2031-SAY, KDC-2031-SG, KDC-2031-SGY Service manual

CD RECEIVER

KDC-2031SA/SAY KDC-2031SG/SGY

SERVICE MANUAL

© 2004-12 PRINTED IN JAPAN B53-0234-00 (N) 1813

SPARE TDF PANEL

MAIN UNIT NAME	TDF PARTS No.	TDF NAME
KDC-2031SA/SAY	Y33-2140-66	TDF-2031SA
KDC-2031SG/SGY	Y33-2140-67	TDF-2031SG

PANEL ASSY

KDC-2031SA/SAY/SG/SGY (A64-3461-02)

VOL
AUD				/AUTO
SET UP
				AME
MONO	FF	SCAN	RDM	REP

LEVER	DC CORD	PLASTIC CABINET ASSY	MOUNTING HARDWARE ASSY
(D10-4589-04) x2	(E30-6413-05)	(A02-2736-03)	(J21-9716-03)

ANTENNA ADAPTOR	ESCUTCHEON
(T90-0523-05)	(B07-3122-01)

This product uses Lead Free solder.

KDC-2031SA/2031SAY

KDC-2031SG/2031SGY

			BLOCK DIAGRAM
J4	L506		ELECTRIC UNIT (X34-)
	FM AGC
ANT
	AM+B
	Q501			Q351,352	J6
	AM AGC			PRE MUTE
			IC10			PRE OUT
				IC4	FM (J/K Type)	: 1800mV
					FM (E Type)	: 1372mV
	SERVO	MPX OUT			AM (J/K Type)	:	600mV
CD or MD					AM (E Type)	:	855mV
	A8V
MECHA		MPX IN			CD/MD RECEIVER : 3600mV
	BU5V			POWER IC
					CHANGER	: 3600mV
AUDIO OUT	800mV		E-VOL	IC6
	1200mV		&
				MUTE LOGIC
			TUNER
			A8V		J1
	IC11					SP OUT
			BU5V	Q51
J2	E2PROM		IC8
			RST IC	SURGE DET
CHANGER	IC7		IC1	Q52
				BU DET		BACK-UP
	RDS
				Q53
AUDIO OUT	DECODER
				ACC DET		ACC
			SYSTEM u-COM			TEL MUTE
						P-ANT
						P-CON

BACK-UP

Q151

IC3

PAN5V

BU5V

POWER SUPPLY IC

SWITCH UNIT (X16-)

PAN5

PAN5V

P-CON

ED1

Q72,73

P-ANT

IC1

SERVO

IC3

Q155

SERVO

SW5V

SW5V

VFD

REMOTE

DSI

IC15

AM+B

AM+B

A8V

AUDIO+B

VFD DRIVER

VFD REG

VCC

S11

with

KEY ILLUMI

BU5V

KEY MATRIX

.......

BU5V

.......

ILLUMI

VOL

MECHA ASSY (X92-)

CD PLAYER UNIT (X32-5750-00)

X1

CLOCK

16.934MHz

MOTHER

PICK-UP (DPU1)

D. GND

IC2

BOARD (X34-)

D. GND

IC1

DOUT

22

CLK

19

4

7

A

12

DATA

18

E

F

Q1

RF AMP

MSTOP

10

C

SERVO

11

B

APC

VREF

MRST

PROCESSOR

2

MUTE L

12

u-COM

IC4

MUTE R

13

REF

LPF

L-ch

8

IC3

Q5,6,D3

R-ch

6

D2

Q4

2

CURR.

TR COIL

VREF

A+5V

8V SW

A8V

9

AMP

5V REG

2

7

FO COIL

A. GND

Q3

A. GND

SW

DM1

MUTE

DRV MUTE

Q2

BU5V

15

2

MOTOR

4

SPINDLE MOTOR

5V SW

DRIVER

D. GND

14

DM2

LOADING

D. GND

LOADING & SLED

2

H

VREF

S3

MOTOR

L

LOE/LIM SW

1

SLED

S. GND

S2

SW +5V

12EJE SW

21

D. GND

S1

LOS SW

20

S7.5V

3

2

S. GND

4

MOTOR

5

LO/EJ

2

KDC-2031SA/2031SAY

KDC-2031SG/2031SGY

COMPONENTS DESCRIPTION

● ELECTRIC UNIT (X34-3412-7x)

Ref. No.	Application / Function	Operation / Condition
IC1	SYSTEM -COM	System control.
IC3	POWER SUPPLY	DC5Vx2, 7.9Vx1, 8.1Vx1, 10.3V, P.CON, P-ANT output.
IC4	POWER IC	Audio signal amplifier.
IC6	MUTE LOGIC	Mute control.
IC7	RDS DECODER	For other models.
IC8	RESET	“L” when detection voltage goes below 3.6V.
IC10	E-VOL & TUNER	E-VOL, Tuner, Stereo decode.
IC11	E2PROM	Saves and writes tuner adjustment data.
IC15	VFD REGULATOR	11.3V output voltage for LED and VFD.
Q51	SERGE DET	“ON” when the base goes “H”.
Q52	BU DET	“ON” when the base goes “H”.
Q53	ACC DET	“ON” when the base goes “H”.
Q71	SERVO+B CONTROL SW	“ON” when the base goes “H”.
Q72,73	SERVO+B AVR	Output voltage level : 7.5V.
Q74	IC3 CONTROL SW	“ON” when the base goes “H” (Output voltage : 10.3V).
Q151	PANEL 5V SW	“ON” when the base goes “L”.
Q155	DSI ILLUMI SW	“ON” when the base goes “L”.
Q252	IC4 STBY SW	“ON” when the base goes “L”.
Q330	Q351, 352 MUTE DRIVER	“ON” when the base goes “L”.
Q351	Lch PRE MUTE SW	Pre-output is muted when the base goes “H”.
Q352	Rch PRE MUTE SW	Pre-output is muted when the base goes “H”.
Q501	AM RF AMP	Adjusts for AM-RF gain.

● CD PLAYER UNIT (X32-5750-00)

	Ref. No.	Application / Function	Operation / Condition
			Generation of RF signal based on the signals from the APC circuit and pickup, and
	IC1	RF AMPLIFIER responding	generation of servo error (focusing error and tracking error) signals.
		to CD-RW	Detection of dropout, anti-shock, track crossing and off-tracking conditions, included
			gain control function during CD-RW.
			Focusing, tracking, sled and spindle servo processing.
	IC2	CD SIGNAL PROCESSOR	Automatic adjustment (focusing, tracking, gain, offset and balance) operations.
		built-in -COM	Digital signal processing (DSP, PLL, sub-codes, CIRC error correction, audio data
			interpolation processing) operations, and microcomputer function.
	IC3	4ch BTL DRIVER	Focusing coil, tracking coil, spindle motor and sled motor driver, disc loading and
			eject operation.
	IC4	L.P.F. (LOW PASS FILTER)	2nd low pass filter for audio signals.
	Q1	APC (AUTOMATIC POWER CONTROL)	LD power control.
	Q2	DIGITAL +5V SW	“ON” When P. ON signal goes “L”.

3

KDC-2031SA/2031SAY

KDC-2031SG/2031SGY

COMPONENTS DESCRIPTION

Ref. No.	Application / Function	Operation / Condition
Q3	Q4 SW	“ON” When P. ON signal goes “L” (SW+5V is ON).
Q4	ANALOG +8V SW	“ON” When P. ON signal goes “L” (Q3 is ON).
Q5, 6	CURRENT AMP	Current driver.

● SWITCH UNIT (X16-294x-xx)

Ref. No.	Application / Function	Operation / Condition
IC1	VFD DRIVER
IC3	REMOTE SENSOR
Q1	GREEN LED SW	“ON” when the base goes “H”.
Q2	RED LED SW	“ON” when the base goes “H”.
Q21	PAN SW5V	“ON” when the base goes “H”.

MICROCOMPUTER’S TERMINAL DESCRIPTION

● SYSTEM -COM : IC1 on X34- (ELECTRIC UNIT)

	Pin No.	Active	Pin Name	I/O	Application	Processing Operation
		(H/L)
	1		DC ERR	I	DC offset detection input
	2		LINE MUTE	I	Phone detection	NAVI MUTE : Over 2.5V, TEL MUTE : Below 1V
	3		ROTARY CW	I	Rotary encoder input
	4		AVSS	-
	5		TUN TYPE1	I	E-VOL setting switch	Refer to “TUN TYPE” on the TRUTH TABLE
	6		TUN TYPE2	I	E-VOL setting switch	Refer to “TUN TYPE” on the TRUTH TABLE
	7		AVREF1	-
	8		VFD DATAF	I	Data input from VFD driver
	9		VFD DATAS	O	Data output to VFD driver
	10		VFD CLK	O	Clock output to VFD driver
	11	L	VFD RST	O	Reset output to VFD driver	Display OFF, Key reset, TDF panel OFF : L
						Display ON, Key scan : H
	12		VFD CE	O	Chip enable output to VFD driver
	13		ROTARY CCW	I	Rotary encoder input
	14	L	TDF DET	I	TDF panel detection	TDF panel OFF : H, TDF panel ON : L
	15		PWIC BEEP	O	Beep output
	16~19		NC	-
	20	L	TUN ADJ	I	For adjusting IC10	Adjustment=H, PS1-1,2=L, PS1-3=Hi-Z,
						PS2-1,2=Hi-Z, TUN DATA, CLK=Hi-Z
	21		TUN SD	I	Tuner search stop output	H : Station exists, L : Station does not exist

4

KDC-2031SA/2031SAY

KDC-2031SG/2031SGY

MICROCOMPUTER’S TERMINAL DESCRIPTION

	Pin No.	Active	Pin Name	I/O	Application	Processing Operation
		(H/L)
	22~24		NC	-
	25		AUD SDA	I/O	Volume + tuner I2C data input and output
	26		AUD SCL	I/O	Volume + tuner I2C clock input and output
	27	H	PWIC STBY	O	Power IC standby output	Power IC ON : H, Power IC OFF : L
	28	H	VOL MUTE	O	E-VOL mute output	L : Mute OFF, Hi-Z : Mute ON
	29	L	PWIC MUTE	O	Power IC mute output	Power OFF : L, Standby : L, Tel mute : L
	30		TUN FANC OUT	O	Tuner block (inside the -com) check	OK : L, NG : H
	31		RESET2	O	Mute for reset	Output L
	32		NC	-
	33		VSS1	-
	34		NC	-
	35	L	ACC DET	I	ACC detection	ACC exists : L, ACC does not exist : H
	36	L	BU DET	I	Momentary power-down detection	BU exists : L
						BU does not exist (Momentary power-down) : H
	37		NC	-
	38		PS2-2	O	Power supply control output	Refer to “POWER IC CONTROL” on the TRUTH TABLE
	39		PS2-1	O	Power supply control output	Refer to “POWER IC CONTROL” on the TRUTH TABLE
	40		PS1-1	O	Power supply control output	Refer to “POWER IC CONTROL” on the TRUTH TABLE
	41		PS1-2	O	Power supply control output	Refer to “POWER IC CONTROL” on the TRUTH TABLE
	42		PS1-3	O	Power supply control output	Refer to “POWER IC CONTROL” on the TRUTH TABLE
	43,44		NC	-
	45		CD MUTE	I	CD mute request	L : Mute request
	46	L	CD MSTOP	O	CD mecha u-com stop	H : mecha -com operates, L : mecha -com is stopped
	47		CD LOE LIM SW	I	CD detection (chucking switch)	H : Loading is finished, L : Disc does not exist
	48		CD LOEJ	I/O	CD motor control	Refer to “CD MECHA CONTROL OPERATION”
						on the TRUTH TABLE
	49		CD MOTOR	O	CD motor control	Refer to “CD MECHA CONTROL OPERATION”
						on the TRUTH TABLE
	50		NC	-
	51	L	CD MRST	O	CD mecha -com reset	H : Normal condition, L : Reset
	52		CD SCL	I/O	CD mecha I2C clock output
	53		CD DISC12 SW	I	12cm CD detection
	54		CD LOS SW	I	CD loading detection
	55		CD SDA	I/O	CD mecha I2C data input and output
	56		OEM DISP CE	I/O	External display chip enable	External display
	57		OEM DISP CLK	I/O	External display clock	External display
	58		OEM DISP DATA	I/O	External display chip data	External display
	59		DSI	O	DSI control	DSI ON : H, DSI OFF : L, TDF DET=H (DSI blinks)
	60	L	RESET	I

5

KDC-2031SA/2031SAY

KDC-2031SG/2031SGY

MICROCOMPUTER’S TERMINAL DESCRIPTION

	Pin No.	Active	Pin Name	I/O	Application	Processing Operation
		(H/L)
	61		NC	-
	62	L	PON FL	O	VFD power supply ON	VFD ON : H, VFD OFF : L
						TDF DET H (DSI blinks) : L, TDF DET L : H
	63		KEY REQ	I	Communication request from VFD driver	L : Key input
	64		NC	-
	65		REMOTE	I	Remote control input
	66		NC	-
	67		VSS0	-
	68		VDD1	-
	69		X2	-
	70		X1	-
	71		TEST	-
	72		XT2	-
	73		XT1	-
	74		VDD0	-
	75		AVDD	-
	76~78		TYPE 3~TYPE 1	I	Destination switch
	79		NC	-
	80		TUN SMETER	I	Tuner S-meter input

● TRUTH TABLE

• TUN TYPE

		TYPE 1	TYPE 2
	General models commercially-designated as pure KENWOOD brand (Initial value)	L	L
	Initial value setting

• POWER SUPPLY IC (IC3) CONTROL

SEL1 (Pin No. 11)

PS1-2	PS1-3	PS2-1	ILLUMI	P-CON	P-ANT
L	L	L	OFF	OFF	OFF
L	L	H	ON	OFF	OFF
H	L	H	ON	ON	OFF
H	H	H	ON	ON	ON
SEL2 (Pin No. 12)
PS1-1	PS2-2	AUDIO	SW5	AM
L	L	OFF	OFF	OFF
H	L	ON	ON	OFF
H	H	ON	ON	ON

• CD MECHA CONTROL OPERATION

CD LOEJ	CD MOTOR	CD MECHA OPERATION
L	H	Load
H	H	Eject
Hi-Z	L	Stop
Hi-Z	H	Brake

6

KDC-2031SA/2031SAY

KDC-2031SG/2031SGY

MICROCOMPUTER’S TERMINAL DESCRIPTION

● CD MECHANISM -COM : IC2 on X32- (CD PLAYER UNIT)

	Pin No.	Active	Pin Name	I/O	Application	Processing Operation
		(H/L)
	1		TVD	O	Traverse drive output (PWM output).
	2		SPL	O	Spindle motor drive output (PWM output).
	3		NC	-	No connection.
	4		PWM	O	Multipurpose PWM output.
	5		TBAL	O	Tracking balance adjustment output (PWM output).
	6		FBAL	O	Focusing balance adjustment output (PWM output).
	7		NRFDET	I	RF detection signal input.	L : Detection
	8		OFT	I	Off-tracking signal input.	H : Detection
	9		BDO	I	Drop-out signal input.	H : Detection
	10		LDON	O	Laser-on signal output.	H : Focus ON
	11		DSLB	O	DSL balance output.
	12		DVDD1	-	Power supply for digital circuit.
	13		DVSS1	-	GND for digital circuit.
	14		AVSS2	-	GND for analog circuit.	For DSL, PLL and A/D converter
	15		DSLF	I/O	Loup filter for DSL and bias output for ARF.
	16		ARF	I	RF signal input.
	17		RFSW	I	DSL circuit time constant switch.
	18		PLLF	I/O	Loup filter for PLL.
	19		PLLF2	I/O	Loup filter character switch for PLL.
	20		IREF	I	Reference current input.
	21		RFENV	I	RF envelope signal input.
	22		TRCRS	I	Tracking cross signal input.
	23		TE	I	Tracking error signal input.
	24		FE	I	Focusing error signal input.
	25		AVDD2	-	Power supply for analog circuit.	For DSL, PLL and A/D converter
	26		AVSS1	-	GND for analog circuit.	For Lch/Rch audio output
	27		OUTR	O	Rch audio output.
	28		AVDD1	-	Power supply for analog circuit.	For Lch/Rch audio output
	29		OUTL	O	Lch audio output.
	30		DVSS3	-	GND for digital circuit.
	31		CSEL	-
	32		NC	-	No connection.
	33		ASEL	-
	34		MSEL0	-
	35		MSEL1	-
	36~39		NC	-	No connection.
	40		VREFP	-	Reference power supply input for A/D converter.
	41		HOT	-

7

KDC-2031SA/2031SAY

KDC-2031SG/2031SGY

MICROCOMPUTER’S TERMINAL DESCRIPTION

	Pin No.	Active	Pin Name	I/O	Application	Processing Operation
		(H/L)
	42		8EJE SW	-
	43		12EJE/SDET SW	-
	44		LOE/LIM SW	I	Loading-end detection /	H : Loading-end detection
					Pick-up inner circumference detection.	L : Pick-up inner circumference detection
	45~49		NC	-	No connection.
	50		DVDD2	-	Power supply for digital circuit.
	51		X1	I	Main clock input.
	52		X2	O	Main clock output.
	53		DVSS2	-	GND for digital circuit.
	54		XSUB1	-
	55		NC	-	No connection.
	56		TEST1	-	Test terminal.	Normal condition : “H” fixed
	57		TEST2	-	Test terminal.	Normal condition : “H” fixed
	58,59		NC	-	No connection.
	60		DRV MUTE	O	Driver mute control.	L : Mute ON, H : Mute OFF
	61	L	MUTE L	O	Audio Lch mute output.
	62	L	MUTE R	O	Audio Rch mute output.
	63	L	RST	I	LSI reset input.
	64		OCD CLK	-
	65	L	MSTOP	I	Standby detection.
	66		DATA	I/O	I2C bus data line (Communication line to system -com).	During serial writer is connected.
	67		SBIO	I	Data input.	During serial writer is connected.
	68	L	CLK	I/O	I2C bus clock line (Communication line to system -com).	During serial writer is connected.
	69		TX	O	Digital audio interface signal output.
	70		NC	-	No connection.
	71		XSEL	-
	72		MCNT	I	Loading control / Eject control.	L : OFF (Host control), H : Mecha -com control
	73		P. ON	O	Audio & Servo power supply control.	L : Power supply ON. H : Power supply OFF
	74,75		NC	-	No connection.
	76		CD-RW	O	CD-RW control.	H : CD-RW, L : Normal disc
	77		NC	-	No connection.
	78		DVDD3	-	Power supply for digital circuit.
	79		FOD	O	Focusing drive output (PWM output).
	80		TRD	O	Tracking drive output (PWM output).

8

KDC-2031SA/2031SAY

KDC-2031SG/2031SGY

TEST MODE

How to enter the test mode

While simultaneously press PRESET “1” key and PRESET “3” key, press “RESET” button.

How to release the test mode

Press “RESET” button. (The release cannot be achieved in the conditions of POWER OFF and ACC OFF.)

Initial conditions of the test mode

•The source is “STANDBY”.

•The displays all lit up.

•The volume is at –10dB (The display shows “30”.)

•LOUD is “OFF”.

•SYSTEM Q is “NATURAL”.

•BEEP is sounded at all time with the key depressed for less than 1 second.

Special displays when all indicator lights are lighted

When “PRESET” keys are pressed while all indicators for the

STANDBY sources are lighted, the following displays will ap-

pear.

PRESET	• Version display (4 digits : month, date)
“1” key	(4digits : hour, minute)
	(Display) : XXXX xxxx
PRESET	• Serial number display (4 digits) (4 digits)
“2” key	(Display) : XXXX xxxx
PRESET	• When pressed for less than 1 second : POWER ON
“3” key	time display (STANDBY source time is not counted.)
	(Display) : _ _ _ X xxxx	MAX 60,000 (hours)
	* The display is cleared by pressing the key for more
	than 2 seconds.
PRESET	• When pressed for less than 1 second : CD operation
“4” key	time display
	(Display) : _ _ _ X xxxx	MAX 60,000 (hours)
	* The display is cleared by pressing the key for more
	than 2 seconds.

PRESET	• When pressed for less than 1 second : CD EJECT
“5” key	number display
	(Display) : _ _ _ X xxxx	MAX 60,000 (times)
	* The display is cleared by pressing the key for more
	than 2 seconds.
PRESET	• When pressed for less than 1 second : Panel open/
“6” key	close number display
	(Display) : _ _ _ X xxxx	MAX 600,000 (times)
	* The display is cleared by pressing the key for more
	than 2 seconds.
“FM”	• ROM CORRECTION version display
key	(Display)
	Effective : Rxxx (x : number)
	Not effective (When not able to read) : R – – –
	Not effective (When version is different) : R
“AM”	• IC10 adjustment status (Refer to “ADJUSTMENT” on
key	the following page.)
	(Display)
	Adjustment complete : E2OK
	Adjustment not completed : E2ER
	Communication error : ICER
	* When other than “E2P _ OK _ _” , Pin No. 30 will
	become “H”.
“ ”	• Mechanism error detection status
key	• Communication error →	Error No. 1 → Error No. 2 →
	Error No. 3 → Communication error (Error No. 1 is the
	most recent error.)
	(Display)
	Communication OK : ICOK
	Communication error : ICER
	Not detected : En – –	(n : 1~3)
	Detected : En ( : error code)
	* The display is cleared by pressing the key for more
	than 2 seconds.

9

KDC-2031SA/2031SAY

KDC-2031SG/2031SGY

SPECIAL MODE ADJUSTMENT

● DC offset error detection confirmation mode

Confirmation mode :

While depressing PRESET “3” key and PRESET “6” key simultaneously, press on the “RESET” button.

(Display) Detected : DCER

Not detected : DCOK

*By pressing “CLK” key while “DCER” is being displayed, detection status is cleared. This will result in the display of “DCOK”.

Release Method : Press “RESET” button.

● Mechanism memory clear confirmation mode

Confirmation mode :

While depressing “ATT” key and “Q” key simultaneously, press “RESET” button.

(Display) : MCLR

*Two seconds after the confirmation mode boots up, Mechanism memory clear as a result is displayed.

(Display) Clear status display normal completion : CD _ O Clear status display abnormal completion : CD _ –

Release Method : Press “RESET” button.

After replacing the following parts, adjust as follows.

REPLACED PARTS		ADJUSTMENT ITEMS
Ref. No.	Function / Parts name	1st AM MIX	2nd AM MIX	FM antenna
IC10	E-VOL & TUNER	YES	YES	YES
IC11	E2PROM	YES	YES	YES
L507	VCO COIL	YES	YES	YES
L508	1st AM MIX IFT	YES	-	-
L509	2nd AM MIX IFT	-	YES	-
L518	FM ANTENNA COIL	-	-	YES
D504	VARIABLE	YES	YES	YES
	CAPACITANCE DIODE
D506	VARIABLE	YES	YES	YES
	CAPACITANCE DIODE
X501	CRYSTAL RESONATOR	YES	YES	YES

● 1st AM MIX / 2nd AM MIX ADJUSTMENT

ADJUSTMENT POINT : L508 (1st AM MIX) / L509 (2nd AM

MIX)

VOLTAGE VALUE CHECK POINT : S-METER check land (X34-)

Adjust so that S-METER voltage value becomes maximum.

• SG setting

DESTINATION	FREQUENCY	MODULATION	ANTENNA INPUT
Europe	999kHz	OFF	35dB V (EMF)
Except Europe	1000kHz	OFF	35dB V (EMF)

● FM ANTENNA ADJUSTMENT

ADJUSTMENT POINT : L518

VOLTAGE VALUE CHECK POINT : S-METER check land (X34-) Adjust so that S-METER voltage value becomes maximum.

• SG setting

DESTINATION	FREQUENCY	MODULATION	ANTENNA INPUT
Europe	87.5MHz	OFF	5dB V (LOAD) or
			11dB V (EMF)
Except Europe	87.9MHz	OFF	5dB V (LOAD) or
			11dB V (EMF)

10