Kenwood KDC-2023, KDC-2024-SA, KDC-2024, KDC-2024-SG, KDC-2024-SYA Service manual

CD RECEIVER

KDC-2023 KDC-2024SA/SG/SYA/SYG KDC-2094YA/YG KDC-222/S

KDC-3023

SERVICE MANUAL

© 2002-11 PRINTED IN JAPAN B53-0004-00 (N) 3379

CD mechanism operation description is not in this sarvice manual.						CD mechanism extension cord : WO5-0618-00
Please, refer to sarvice manual X92-4030-0x (B51-7867-00).
Panel assy		Escutcheon		Panel assy			Escutcheon
(A64-2867-02): KDC-222		(B07-3060-02): KDC-222		(A64-2870-02): KDC-2023			(B07-3001-02): KDC-2023
(A64-2868-02): KDC-222S		(B07-3022-02): KDC-222S		(A64-2873-02): KDC-3023			(B07-3022-02): KDC-3023

CD MD-Changer Control

DIGITALAUDIO

M. RDM

Panel assy	Escutcheon	Panel assy	Escutcheon
(A64-2878-02): KDC-2024SA/SG/SYA/SYG	(B07-3001-02): KDC-2024SA/SG/SYA/SYG	(A64-2884-02): KDC-2094YA/YG	(B07-3001-02): KDC-2094YA/YG
			WIDE BAND
DIGITALAUDIO		DIGITALAUDIO
			ADJ AUTO AME

DC cord	DC cord(ISO)	Mounting hardware assy	Plastic cabinet assy
(E30-4784-05)	(E30-4790-05)	(J21-9716-03)	(A02-1486-13)

Lever	Antenna adaptor	Screw set	Screw set
(D10-4589-04)x2	(T90-0523-05)	(N99-1719-05)	(N99-1610-15)

Depends on model. Refer to the parts list

2

	FM+B			A8V				FM(J,K) : 1800mV
	Q502		IC10				Q223,224	FM(E) : 1372mV	CD : 3600mV
							PRE	AM(J,K) : 600mV		PRE
ANT	FM AGC		FM AGC OUT					AM(E) : 855mV	CH : 3600mV
							MUTE	IC4		OUT
	AM+B
	Q501
	AM AGC		AM AGC OUT				IC8	POWER IC		SP
				TUNER,MPX &						OUT
	CD	SERVO		E-VOL.			MUTE	MUTE
							LOGIC
				OUT
		BU5V
		A8V		TUNER
	AUDIO OUT	1200mV	CH					Q10
								BU		BACK
			CD
	12EJE							DET		UP
	LO/S	1200mV		IC6				ACC
	SCLK					IC12
	SDA						EEP-ROM	Q20
	8EJE
	MUTE							DET		ACC
	RST			RDS	BU5V		IC11
	STOP
				DECODER			RESET		IC7
	LO/EJ
	MO						IC		POWER
	LOE/LIM
									SUPPLY IC
			IC1
									P-CON	P-CON
	CHANGER								P-ANT	P-ANT
	AUDIO OUT							Q51,55
	RST			MI-COM			SERVO	SERVO	VCC
	REQ C
	CLK								SW1
	DATA H								SW2
	CH-CON							Q50
	REQ H							SW5V	BU5V
	DATA C						SW5V
	MUTE							BU5V
									FM+B
		BACK UP						FM+B
								AM+B	AM+B
				BU5V			SW5V	A8V	AUDIO+B
									ILLUMI
						IC2		BACKLIGHT
							KEYILLUMI
			LCD	LCD DRIVER			REMOCON
				WITH
				KEY MATRIX

	2023,-KDC
DIAGRAM BLOCK	2094YA/YG, 2024A/SG/SYA/SYG,
	222/S,3023

KDC-2023, 2024A/SG/SYA/SYG, 2094YA/YG, 222/S,3023

COMPONENTS DESCRIPTION

● SWITCH UNIT (X16-1460-xx/2370-12)

Ref.No.	Application/Functions	Operation/Condition/Compatibility
IC1	LCD driver & key matrix
IC2	Remote Sencer
Q1	Key scan start	When Q1 base goes Lo, key scan start.

● ELECTRIC UNIT (X25-9600-xx/9612-7x)

Ref.No.		Application/Functions	Operation/Condition/Compatibility
IC1	System control µ-com		System µ-com
IC4	Power amplifire		E-Vol output encoder power amplification for speaker.
IC7	Power supply (Multi AVR)		-
			When a pin 1, 2, or 13 is "H", MUTE turns on
IC8	MUTE Logic		When a pin 3, 4, or 5 is "H", P-AMP mute turns ON.
			Changer is RESET when a pin 9, 10, or 11 is "L".
IC10	Tuner & E-Vol.		FM/AM tuner & stereo decoder & E-Vol.
IC11	Power on reset		When B.U. 5V voltage is less than 3.5V, power reset.
IC12	E2P-ROM		Writing and read-out of adjustment data for a tuner
Q10	B.U. detector		BU on (base "H") : Collector "H"
Q20	A.C.C	detector	ACC ON (base : "H") : Collector "L"
Q40	MUTE	driver	Base "L" : Mute on (collector "L")
Q50	SW 5V		Base "L" : SW5V on
Q51	SERBO AVR control		Pin 2 "H" : Serbo on (pin 4 "H")
Q55	SERBO AVR		Base "H" : Serbo on
Q70	Surge detector		Base "H" : Surge detect
Q101	DSI driver		Base "H" : DSI on
Q102	PANEL 5V SW		Panel attch : PAN5V on
Q223,224	MUTE		Base "H" : Mute on
Q501	AM RF amplifire		Base "H" : Gain UP
Q502	FM RF amplifire		Gate "H" :Gain UP

3

KDC-2023, 2024A/SG/SYA/SYG, 2094YA/YG, 222/S,3023

MICROCOMPUTER'S TERMINAL DESCRIPTION

● SYSTEM MICROCOMPUTER uPD780058GCxxx (X25 : IC1)

	Pin No.	Name	I/O	Description		Processing Operation
	1	TDF DET	I	Panel detection	H:Panel detached			L:Panel attached
	2	8EJE SW	I		H:Eject is completed
					Except 8cm CD model:always output L
	3	NC	O	Not used (out put L)
	4	Avss
					H:Panel detached			L:RESET
	5	L-RST	O	LCD driver RESET	∆3 normal H , Power off L
					When 7seg model,output L
	6	L-CE	O	LCD driver selection	H:Select (panel communication)
					When panel attached,output L
	7	AVREF1
	8	NC		Not used (connected to 9pin)
	9	IC10-DATA	I/O	IC10,E2PROM data communication	∆3 non communication : H
	10	IC10-CLK	O	IC10,E2PROM clock communication	∆3 non communication : H
					Non communication : H
	11	L-DATAL	I	Data input from the LCD driver	When panel detached : L
					∆3 Pull down on X25 unit,Pull up on X16 unit
	12	L-DATAS	O	Data output to the LCD driver	When panel detached , output L
	13	L-CLK	O	Clock output to the LCD driver	When panel detached , output L
	14	R-DATA	I	Data input from the RDS	Except RDS model : output L
	15	R-QUAL	I	Quality input from the RDS	Except RDS model : output L
	16	CH-DATAC	I	Data input from the changer (new 5L)	Except changer model : output L
	17	CH-DATAH	O	Data output to the changer (new 5L)	When non communication ,last data keeping
					Except changer model : output L
	18	CH-CLK	I/O	Clock input/output with the Changer (new 5L)	Check the old and new
					Except changer model : output L
	19	CH-REQH	O	Request output to the changer (new 5L)	L:Requset
					Except changer model : output L
	20	NC	O	Not used (output L)
	21	AFS	O	Noise detection time constant switching terminal	H:Normal	L:FM/AM seek and AF search
					∆3 (When tuner SRC auto zero , L)
	22-24	NC	O	Not used (output L)
	25	CH-CONT	O	Changer control	H:Changer on		L:Changer off
					Except changer model : output L
	26	TYPE REF	O	5V lines output for destination setting	H:During destination reading
	27	SD	I	Tuner SD input	H:Station detected
	28	NC	O	Not used (output L)
	29	TYPE2	I	Destination type selection terminal 2	Refer to destination type list.
	30	TYPE1	I	Destination type selection terminal 1	Refer to destination type list.
	31	TYPE0	I	Destination type selection terminal 0	Refer to destination type list.
	32	TUNER-TYPE1	I	Destination available/genuine model rool off	H:genuine model 1			L:available model
	33	Vss1
	34	TUNER-TYPE0	I	Destination available/genuine model noise cancel	H:genuine model 0			L:available model
	35	MUTE	O	Mute (E.Vol,Preset) control	H:mute on	L:mute off
					Power off after that 15 second L
	36	M-DATA	I/O	Data input/output with the CD mechanism	∆3 non communication : H
	37	M-CLK	O	Clock output to the CD mechanism	∆3 non communication : H
					When adjustment = H
	38	ADJ	O	Tuner lines adjustment	PS1-0,1=L		PS1-2,2-0,1=Hi-z
					IC10-DATA,CLK=Hi-z
	39	P-MUTE	O	Power IC mute control	H:mute off	L:mute on
					Power off after that 15 second H
	40	SVR	O	Power IC servo control	H:When momentary power down detected
					L:Nomal
	41	P-STBY	O	Power IC standby control	H:Power IC ON		L:Power IC OFF
	42	SW5V	O	SW 5V control	H:SW5V OFF		L:SW5V ON
					Power off after that 10 second H
4

KDC-2023, 2024A/SG/SYA/SYG, 2094YA/YG, 222/S,3023

MICROCOMPUTER'S TERMINAL DESCRIPTION

Pin No.

Name

I/O

Description

Processing Operation

43

B.U-DET

I

Back up detection terminal

H:power down

L:B.U. on

44

ACC-DET

I

ACC detection terminal

H:ACC OFF L:ACC ON

Power supply IC SW1 control 0

45

PS1-0

O

BA4911 SW1

Power supply IC output

Audio 8V,P-CON

PS1-2

PS1-1

PS1-0

A8V

P-CON

P-ANT

L

L

L

STANBY

Power supply IC SW1 control 1

46

PS1-1

O

L

L(H)

H(L)

ON

OFF

OFF

Audio 8V,P-CON

L

H

H

ON

ON

OFF

47

PS1-2

O

Power supply IC SW1 control 2 P-ANT

H

H

H

ON

ON

ON

48

PS2-0

O

Power supply IC SW2 control 0

BA4911 SW2

Power supply IC output

ILL,FM,AM

PS2-1

PS2-0

ILLUMI

FM

AM

L

L

STANBY

49

PS2-1

O

Power supply IC SW2 control 1

L(H)

H(L)

ON

ON

OFF

H

H

ON

OFF

ON

ILL,FM,AM

50

BEEP

BEEP

H:Light on

L:Light off

51

DSI

O

DSI control

When panel attached,output L

When panel detached,flashing at the panel (H/L)

FIX model is output L

52

NC

O

Not used (out put L)

53

NC

O

Not used (out put L)

54

LOE/LIM SW

I

CD mechanism down&limit detection

H:Chucking detection L:Normal

55

MO SW

O

CD mechanism loading motor control output

H:Loading,Eject,Break

L:Play

56

LO/EJ

I/O

CD mechanism loading/Eject switching terminal

H:Eject

L:Loading

57

M-STOP

O

Stop output to the CD mechanism

H:Play

L:Stop

58

M-RST

O

Reset output to the CD mechanism

H:Normal

L:CD mechanism reset

59

M-MUTE

I

Mute input from the CD mechanism

H:mute off

L:mute on

60

RESET

Reset input from the System microcomputer

61

REMO

I

Remote control input

62

R-CLK

I

RDS clock input

Except RDS model : output L

H:Changer detection

63

CH-REQC

I

Request input from the changer (new 5L)

L:Request

Except Changer model : output L

64

LOS SW

I

CD mechanism loading's switch detected

H:No disc

L:DISK IN(Loading Start)

65

KEY-REQ

I

Key input detected

H:Key no input

(11pin L connected to the DATA L)

L:Key input (edge key data reading start)

66

12EJE SW

I

12cm disc detected

L:12cm disc

67

Vss0

68

VDD1

69

X2

∆3 MAIN X'tal oscillating circuit

∆3

4.19MHz X'tal connection

70

X1

∆3 MAIN X'tal oscillating circuit

∆3

4.19MHz X'tal connection

71

IC

TEST

72

XT2

Not used

OPEN

73

XT1

74

VDD0

VDD

Connected to VDD

75

AVREF0

A/D converter reference voltage control output,

connection to the 80pin AVCONT

76

S-METER

I

S-meter input

77

NOISE

I

FM noise detection input

∆3

2.5V or greater:NAVI MUTE

78

PHONE

I

2way mute

1.0V or less:TEL MUTE

Except phone mute model : output L

79

NC

O

Not used (out put L)

80

AVCONT

O

A/D converter standard voltage control output

H:During A/D converter active

same timing with PON

5