Kenwood KDC-8026, KDC-MP825, KDC-W7027 Service Manual

CD RECEIVER

KDC-8026
KDC-MP825
KDC-MPV8025
KDC-W7027

SERVICE MANUAL

© 2004-02 PRINTED IN JAPAN
B53-0130-00 (N) 2704

CD mechanism extension cord (24PIN) : W05-0935-00

Panel assy
KDC-8026 (A64-3231-01)

Panel assy
KDC-MPV8025 (A64-3228-01)

Panel assy
KDC-MP825 (A64-3229-01)

Panel assy
KDC-W7027 (A64-3223-01)

* DC cord
(E30-6294-05)
(E30-6295-05)

*Remote controller assy
(A70-2040-05) : RC-505

* Depends on model. Refer to the parts list.

* DC cord
(E30-4942-05)

*Size AA Battery

(Not Supplied)

Escutcheon
(B07-3078-01)

Lever
(D10-4674-04) x 2

TDF PANEL INFORMATION
MODEL PARTS NO. PANEL NAME
KDC-8026
KDC-MP825
KDC-MPV8025
KDC-W7027

Mounting hardware assy
(J21-9823-03)

*Screw set
(N99-1723-05)

Y33-1790-61 TDF-M7000

Screw
(N99-1734-05)

* Antenna adaptor
(T90-0552-05)

Plastic cabinet assy
(A02-2731-13)

KDC-8026/MP825
KDC-MPV8025/W7027

BLOCK DIAGRAM

(X34- )

TUNER

AUDIO OUT

S-METER

CD

CH

BU5V

Q501

EEP5V

IC1

EEPROM

TDF UNIT
(X16-208)

DISPLAY

UNIT
(X16-254)
(X16-255)

SWITCH UNIT

(X16-256)

Q303,304

AM+B

8V

BU5V
8V
SERVO
CD4.7V

BACK UP

IC9

REMO

8V 8V

BUFFER

IC14

RDS
DECODER

EEPROM

SW5V

IC7

LEVEL
SHIFT

IC11

u-COM

ROT ARY
ENCODER

SW5V

LEVEL
SHIFT

IC8

BU5V

IC2

IC4

IC10

FL

KEY

KEY MATRIX

BPF

IC1

MASK
ROM

FLASH
ROM

BPF

SW5V

2.5V

LEDLED

AGC

AGC

8V

BUFFER

SYSTEM
MICROPROCESSOR

ILL+

RESET SW

PANEL5

Q6,10

PANEL
SW5V

IC6

3.3V

Q5

SW3.3V

Q4

FL3.3V

Q2,3

FL+B

IC2

FM
AM
CD
CH

QUAL

E-VOL

MPX

KEY ILL

9V

9V

9V

AUX IN

PRE OUT
(SUB WOOFER)

PRE OUT
(REAR)

PRE OUT
(FRONT)

SP OUT (FL)
SP OUT (FR)
SP OUT (RL)
SP OUT (RR)

WIRED REMO/
OPEL DISP I/F

EXT.AMP.CON

TEL MUTE

ACC

BACK UP

8V

&

8V

IC15

MOTOR

FL+B

FAC

IC5

SYSTEM
E'S+

IC20

FOCUS
SW

IC8

SERVO

PANEL
MECHA

SW5V

DC/DC

WOW

RESET

IC16

MOTOR
DRDR

IC6

BU5V

IC9

8V

8V

MUTE
DRIVER

Q207,208

PRE MUTE

Q203,204

PRE MUTE

Q205,206

PRE MUTE

IC4

POWER
IC

BU5V

IC18

Q23,24

ANT-CON ANT CON

Q25

EXT AMP

Q26

DIMMER DIMMER

TEL MUTE

Q29

ACC DET

Q27

B.U DET

BU5V

SW5V

PANEL5V

SW14V

DC/DC A8V

9V

SERVO

CD4.7V

IC13

IC12

IC11

P-CON P CON

Q1,2

BU5V

Q3,601

SW 5V

Q502,503

PANEL
5V

Q4,5

SW 14V

Q6-8

A8V

Q9,602

SERVO

Q11-14

FL+B

IC19

SW REG

OP AMP

OP AMP

OP AMP

2

KDC-8026/MP825
KDC-MPV8025/W7027

COMPONENTS DESCRIPTION

● SUB CIRCUIT UNIT (X16-2080-10)

Ref No. Application / Functions Operation / Condition / Compatibility

IC1 E2PROM E2PROM for security

● DISPLAY UNIT (X16-2540-10)

Ref No. Application / Functions Operation / Condition / Compatibility

IC1 Driver LCD driver (Include KEY input function)

IC2 Driver LCD driver

IC3 Remote control IC For Remote control sensor

Q1 SW Key scan start SW “ON” when Q1 base level goes L

Q2 Red LED SW Red LED is turned on when Q2 base level goes H

Q5 VLCD AVR Reference voltage

Q6 SW Power supply control SW “ON” when base level goes L

Q11 Dimmer control LCD back light control “OFF” when Q11 base level goes L

D26 VLCD AVR Reference voltage

● DISPLAY UNIT (X16-2550-10)

Ref No. Application / Functions Operation / Condition / Compatibility

IC1 Driver LCD driver (Include KEY input function)

IC2 Driver LCD driver

IC3 Remote control IC For Remote control sensor

IC4 D/A converter For Variable illumination control

Q1 SW Key scan start SW ON when Q1 base level goes L

Q2 Red LED SW Red LED is turned on when Q2 base level goes H

Q5,D26 VLCD AVR Reference voltage

Q6 SW Power supply control SW ON when base level goes L

Q11-16 Illumination control Variable illumination control transistor

Q62-64 Illumination control Variable illumination control transistor

● SWITCH UNIT (X16-2560-11)

Ref No. Application / Functions Operation / Condition / Compatibility

Q1 DSI LED SW DSI LED blinks when Q1 base level goes H/L

Q2 KEY Illumination SW (Green) KEY Illumination SW “ON” when the Q2 base level goes H

Q3 KEY Illumination SW (Red) KEY Illumination SW “ON” when the Q3 base level goes H

Q4 KEY Illumination SW (Blue) KEY Illumination SW “ON” when the Q4 base level goes H

● CD PLAYER UNIT (X32-5540-00)

Ref No. Application / Functions Operation / Condition / Compatibility

IC1 Mechanism control microprocessor -

IC2 DSP CD signal processor, RF amp, Servo control

IC3 Decoder IC MP3/WMA decoder

IC4 BTL driver Focus, Tracking coil, Feed and Spindle motor driver IC

IC5 AVR SW3.3V AVR

IC6 AVR BU3.3V AVR

3

KDC-8026/MP825
KDC-MPV8025/W7027

COMPONENTS DESCRIPTION

Ref No. Application / Functions Operation / Condition / Compatibility

IC7 AVR BU2.5V AVR
IC8 Selector IC Serial audio data selector
IC9 AVR 3.3V AVR (IC2 DAC part)
Q1,4 Level shift FET Level shift (3.3V - 5.0V)
Q3,5 Level shift TR Level shift (3.3V - 5.0V)
Q6 Level shift TR Level shift (3.3V - 5.0V)
Q7 Level shift TR Level shift (3.3V - 5.0V)
Q8 APC Auto power control
Q9,10 Switching TR Sub beam delay control switch

● ELECTRIC UNIT (X34-3040-10/11/21, X34-3042-71)

Ref No. Application / Functions Operation / Condition / Compatibility

IC1 System control IC System control microprocessor
IC2 E-VOL & tuner IC E-VOL. FM/AM tuner & stereo decoder
IC3 Power supply IC For A8V AVR
IC4 Audio power IC Audio power amplifier
IC5 Power supply IC Switching regulator IC for CD5V
IC7 Reset IC When BU5V line voltage is less than 3.5V, this IC output line is “L”
IC8 Muting logic IC Control for MUTE, P-ANT & RESET muting
IC12 RDS decoder Decode for RDS signal
IC13,14 Motor driver Control for Panel mechanism motor
Q1,2 BU 5V AVR While BU is applied when BU5V regulator output is +5V
Q3 SW5V AVR When Q3base level goes L, SW5V regulator output is +5V
Q4,5 SW14V AVR When Q5 base level goes H, SW14V regulator output is +14V
Q6-8 Audio 8V AVR When Q6 base level goes H, A8V regulator output is +8.4V
Q9,34 Servo +B AVR When Q34 base level goes H, S+B regulator output is +7.4V
Q11~14 Illumination +B AVR When Q11 base level goes H, AVR output is +10.5V
Q23,24 P-ANT SW When Q23 base level goes H, P-ANT SW output is +14V
Q25,26 P-CON SW When Q26 base level goes H, P-CPN SW output is +14V
Q27,28 P-CON protection Protect Q27 by turning on when P-CON output is grounded
Q29 Buffer EX amp control buffer
Q30 Small lamp det. SW When Q30 base level goes H, Q30 turned ON
Q32 BU detector When Q32 base level goes H, Q32 turned ON
Q33 ACC detector When Q33 base level goes H, Q33 turned ON
Q51,52 Muting driver When base level goes L, muting driver is turned ON
Q55,56,59,60
Q63 E2P 5V SW When Q63 base level goes L, E2P 5V is out for E2P ROM
Q102,103 AM +B SW When Q102 base level goes H, AM +B is out to tuner unit
Q104 Buffer Composite signal buffer for RDS

Pre-out muting SW When base level goes H, Pre-output is muted

4