Kenwood KDC-2025, KDC-225, KDC-225-MR Service manual
CD RECEIVER
KDC-225/MR
KDC-2025
SERVICE MANUAL
Panel assy
KDC-225 (A64-3172-02)
D
LOU
AUD
AUTO
AME
OFF
Front glass
KDC-225 (B10-4465-01)
© 2003-12 PRINTED IN JAPAN
B53-0112-00 (N) 764
CD mechanism extension cord (24PIN) : W05-0934-00
+
C.S.
SCRL
-
M.RDM
SCAN
RDM REP
CLK ADJ
DC cord
(E30-6322-05)
(E30-6323-05)
Panel assy
KDC-225MR (A64-3361-02)
D
LOU
AUD
AUTO
AME
Panel assy
KDC-2025 (A64-3305-02)
D
LOU
AUD
AUTO
AME
* Escutcheon
(B07-3097-02)
(B07-3098-02)
Front glass
KDC-225MR (B10-4559-01)
OFF
Front glass
KDC-2025 (B10-4548-01)
OFF
Mounting hardware assy
(J21-9716-03)
SCAN
SCAN
RDM REP
RDM REP
Lever
(D10-4589-04) x 2
M.RDM
M.RDM
CRSC
DISP ADJ
CRSC
CLK ADJ
-
-
Screw
(N84-4016-46)
+
+
Plastic cabinet assy
(A02-1486-13)
Screw set
* Not supplied
(N99-1719-05)
* Depends on model. Refer to the parts list.
* Remote controller assy
(A70-2040-05) : RC-505
TDF PANEL INFORMATION
MODEL PARTS NO. PANEL NAME
KDC-225 Y33-1940-60 TDF-42D
KDC-225MR Y33-1940-62 TDF-42DMR
KDC-2025 Y33-1940-61 TDF-42DB
2
1200mV
DXM-6060
DXM-6560
DXM-6540 : 810mV
: 1200mV
: 1200mV
1Vpp@75
Term.
SWITCH UNIT (X16- )
TUNER
CD/VCD
CH
BUFFER
RDS
DECODER
BUFFER
EEPROM
REMOCON
RESET SW
WITH
LCD DRIVER
KEY MATRIX
LCD
DSI
SYSTEM
MPX
E-VOL
&
ACC DET
TEL MUTE
B.U DET
PRE MUTE
DRIVER
MUTE
POWER
IC
THERMAL
PROTECT
ACC
TEL MUTE
BACK UP
(REAR)
PRE OUT
SP OUT
SURGE DET
SERVOSERVO+B
SW 14V
WIRED REMO
SUPPLY
IC
POWER
ANT CON
P CON
RESET
SW 5V
PANEL 5V
SW5V
ILL SW
ILLUMI
IC7
IC2
IC1
IC4
IC3
IC8
IC1
IC2
SW
ANALOG
AUX IN
AUDIO
PARK SW
PARK SW
MICROPROCESSOR
MECHA+B MECHA +B
IC
VIDEO OUT
IC9
IC6
to VIDEO OUT
TUN SMETER
AUDIO OUT
TUN IFC OUT
TUN SCL
TUN SDA
SW5V
AM+B
A8V
CD DISC8 SW
CD DISC12 SW
CD LOS SW
CD SDA
CD SCL
CD LOE LIM SW
CD MUTE L
CD LOEJ
CD MSTOP
CD MRST
SERVO+B
A8V
BU5V
MECHA+B
LX DATA S
LX MUTE
LX RST
LX REQ M
LX REQ S
LX CLK
LX COM
LX DATA M
BACK UP
RDS QUAL
S-METER
RDS DATA
RDS CLK
FM
AM
MP
LEVEL
CD
QUAL
AFS
CH
SW5V
SW5V
BU5V
DSI
L CLK
L DATAS
L CE
L DATAL
REMO
MUTE
PWIC MUTE
LINE MUTE
ACC DE
B.U DET
PWIC BEEP
RST
BU5V
A8V
SW5V
AM+B
ILLUMI
A8V
BU5V
BU5V
MODE
FM
AM
MP3
E-TYPE
1372mV
855mV
3600mV
K-TYPE
1800mV
600mV
3600mV
PWIC STBY
BU5V
TDF DET
SW5V
AUD SCL
AUD SDA
A8V
PON 5
PARK SW
MUTE PRE
PS2-1
PS1-0
PS2-0
PS1-2
PS1-1
PON CD
A8V
CD MOTOR
CD MUTE R
VIDEO OUT
AUX SW
RDS AFS
RDS NOISE
SW5V
SW5V
L RST
KEY REQ
BU5V
ELECTRIC UNIT (X25-)
KDC-225/225MR/2025
BLOCK DIAGRAM
KDC-225/225MR/2025
COMPONENTS DESCRIPTION
● SWITCH UNIT (X16-2640-11/12)
Ref. No. Application / Function Operation / Condition / Compatibility
IC1 LCD driver Drive for LCD unit
IC2 Remote control IC Receiving for the remote control unit
Q1 KEY scan detector key scan start at base gose “L”.
● ELECTRIC UNIT (X25-9980-11/12/21)
Ref. No. Application / Function Operation / Condition / Compatibility
IC1 System microcomputer
IC2 Electronic volume & N.C.MPX Control for source selector, volume & tone, and FM multiplex detector.
IC3 Power supply IC
Control for TUNER unit, CD mechanism, volume & tone, LCD driver and external CD changer unit
Power supply for the units (Bu5V, Audio8V, FM+B, AM+B, P-con and ANT-con)
SW1 OUT
1.5~3.0V Audio ON
3.5~5.0V Audio P-con ON
7.0V~ Audio P-con, P-ant ON
SW2 OUT
2.0~3.0V Illumination, FM ON
4.0V~ Illumination, AM ON
IC4 Audio power amp IC Amplifier for audio signal to derive for 4channel speakers (50W maximum for each channel)
IC6 Muting control IC Control for timing for mute
IC8 Reset IC When detection voltage goes below 3.5V or less Reset IC output change to “L” signal
Q1 Serge detection
Q2 Backup detection
Q3 ACC detection When ACC voltage supplied output is “L”
Q4 SW 5V When base voltage is “L” Q4 is ON
Q21,24 AVR Servo regulator
Q22 SW Servo SW
Q151 DSI driver
Q201 Buffer amp Noise buffer amp
Q252
Q350 Pre & NF mute SW When base voltage to “L”, drive to pre & NF mute SW (Q351)
Q351 Pre mute SW When base voltage to “H”, muting to the pre Lch or NF Lch line
Q352 Pre mute SW When base voltage to “H”, muting to the pre Rch or NF Rch line
Q401 DSI illumination SW When base voltage to “H”, DSI illumination is light up.
For surge measure of audio power IC
When backup voltage become more than 24V output is “L” (momentary power down) /
When backup voltage become less than 24V output is “H”
When BU voltage supplied output is “L” /
When BU voltage not supplied or momentary power down is detected output is “H”
When base voltage level is “L” DSI LED is light up / When base voltage level is “H” DSI LED
turns off / When panel assy is pull off, cut off the supply to panel 5V AVR.
When base voltage to “L”, for control to power IC function (STAND BY)
3
KDC-225/225MR/2025
COMPONENTS DESCRIPTION
● CD PLAYER UNIT (X32-5400-00)
Ref. No. Application / Function Operation / Condition / Compatibility
Generation of RF signal based on the signals from the APC circuit and pickup, and generation
IC1 RF amplifier adapted for CD-RW of servo error (focusing error and tracking error) signals. Detection of dropout, anti-shock,
track crossing and off-track conditions, included gain control function during CD-RW.
Focusing, tracking, sled and spindle servo processing. Automatic adjustment (focusing,
IC2
IC3 4CH BTL driver
IC4 Low pass filter 2nd low pass filter for audio signals
Q1 APC LD power control
Q2 D.5V SW When P ON signal gose “L”, Q2 is ON
Q3 Q4 SW When P ON signal gose “L” (SW+5V AVR is ON), Q3 is ON
Q4 A.8V SW When P ON signal gose “L” (Q3 is ON), Q4 is ON
Q5 Current driver Current driver
Q6 Current driver Current driver
D1 Protection diode Laser diode protection
D2 Zener diode DAC AVR/LPF reference voltage (A.5V)
D3 Current driver Current driver
CD signal processor built-in MI-COM
tracking, gain, offset and balance) operations. Digital signal processing (DSP, PLL, sub-codes,
CIRC error correction, audio data Interpol ration) operations, and Microcomputer function.
Focusing coil, tracking coil, spindle motor and sled motor driver, disc loading and eject operation.
4
KDC-225/225MR/2025
MICROCOMPUTER’S TERMINAL DESCRIPTION
● SYSTEM MICROPROCESSOR : 784225GC233A (X25 : IC1)
Pin No. Pin Name I/O Description / Processing Operation
1 TUN SMETER I S meter detection input terminal
2 RDS NOISE I FM noise detection input terminal
3 LINE MUTE I Phone Muting signal input terminal (More than 2.5V : NAVI mute, Less than 1.0V : TEL mute)
4AVSS - GND
5L RST O Reset signal output (for LCD driver) H : Light on display, key scan, L : Light out on display, key reset
6L CE O CE output for LCD driver IC
7AVREF1 - BU5.0V
8L DATAL I DATA input terminal from LCD derive IC
9L DATAS O DATA output terminal to LCD driver IC
10 L CLK O CLK output terminal to LCD driver IC
11 TDF DET I Panel assy detect terminal H : Panel assy come off
12 AUX ON O Select for AUX input signal H : AUX, L : Other
13 RDS QUAL I RDS decoder QUAL signal input terminal
14 RDS DATA I RDS decoder Data signal input terminal
15 PWIC BEEP O Beep audio signal output terminal
16 LX DATA S I DATA signal input from EXT. unit
17 LX DATA M O DATA signal output to EXT. unit
18 LX CLK I/O CLK signal input/output to EXT. unit
19 TUN SCL O I2C CLK signal output terminal (for front-end)
20 TUN SDA I/O I2C DATA signal input/output terminal (for front-end)
21 TUN IFC OUT I IFC signal input terminal H : Station detect, L : No detect
22 RDS AFS O Time constant select terminal (for noise detect) H : Receiving, L : FM seek, AF search
23 CD SDA I/O I2C DATA output terminal (for CD mechanism, electric VR)
24 AUD SDA O CLK output terminal (for CD mechanism, electric VR)
25 NC - NC
26 LX RST O Reset signal output to EXT. unit
27 LX CON O Control signal output to EXT. unit H : ON L : OFF
28 LX MUTE I Request signal input terminal from EXT. unit L : Mute ON
29 LX REQ M O DATA signal output to EXT. unit
30 PWIC SVR O SVR control for Audio power IC
31 PWIC STBY O STBY control for Audio power IC H : Power IC ON
32 PWIC MUTE O Muting control for Audio power IC
33 VSS1 - GND
34 ACC DET I ACC detection input terminal L : ACC detect
35 RESET2 O Reset output terminal L : Active
36 MUTE O Muting signal output terminal
37 BU DET I BU detect input terminal L : BU detect
38 PARK SW I Packing condition detect terminal H : OFF, L : ON (PARKING)
39 PS2 1 O Power supply IC control terminal
5
KDC-225/225MR/2025
MICROCOMPUTER’S TERMINAL DESCRIPTION
Pin No. Pin Name I/O Description / Processing Operation
40 PS2 0 O Power supply IC control terminal
41 PS1 0 O Power supply IC control terminal
42 PS1 1 O Power supply IC control terminal
43 PS1 2 O Power supply IC control terminal
44 PON 5 O SW5V/SW14V control output terminal Hi-Z : OFF, L : ON
45 NC - NC
46 PON CD O MP3 power supply control terminal
47 CD DISC12 SW I 12cm CD disc eject SW detection input terminal L : 12cm disc
48 CD MUTE R I Request for muting signal from CD mechanism L : Mute request
49 NC - NC
50 CE MRST O Reset signal output to CD mechanism L : Active
51 CD DISC8 SW I 8cm CD disc eject SW detection input terminal (Not used)
52 CD LOS SW I Loading start SW detection input terminal L : Loading start
53 CD MUTE L I Request for muting signal from CD mechanism L : Mute request
54 NC - NC
55 CD MSTOP O Request signal (Mechanism is STOP) output to CD mechanism L : Active
56 CD LOE LIM SW I Down SW detection from CD mechanism
57 CD LOEJ I/O CD mechanism loading / eject control terminal H : Eject, L : Loading
58 CD MOTOR O CD mechanism motor loading control terminal H : Loading, Eject, Brake, L : Play
59 DSI O Disc guide illumination control terminal H : DSI ON
60 RESET I Reset input terminal L : Active
61 NC - NC
62 KEY REQ I Request for communication to slave unit L : Key input mode
63 RDS CLK I RDS decoder CLK input terminal
64 LX REQ S I DATA signal input from EXT. unit
65 REMO I Remote control signal input terminal
66 NC - NC
67 VSS0 - GND
68 VDD1 - BU5.0V
69 X2 - Main clock input terminal (10MHz)
70 X1 - Main clock input terminal (10MHz)
71 TEST - GND
72 XT2 - Sub clock input terminal (32.768kHz)
73 XT1 - Sub clock input terminal (32.768kHz)
74 VDD0 - BU5.0V
75 AVDD - BU5.0V
76~78 TYPE0~2 I Destination input terminal DXM6540 (SEL0 : Lo, SEL1 : Lo)
79,80 TUN TYPE0,1 I Electric volume condition setting terminal
6
TEST MODE
KDC-225/225MR/2025
1. How to enter test mode
While holding the FM key and PRESET 6 keys, reset the
unit.
All display segments light up when the test mode is entered.
2. How to exit from test mode
Reset the unit.
Turning ACC off, po wer off, momentary power down or panel
detaching does not terminate the test mode.
3. Initial status in the test mode
• Sources : ALL OFF (STAND BY)
• Display : All segments were lit.
•Volume : -10dB (displayed as “30”)
• Loudness : OFF
• CRSC : OFF regardless of the presence of switching function.
•Aux : ON
4. TUNER function
• Forced switching of K3I
Each press of the Preset 6 key in Tuner mode should switch
K3I from AUTO→Forced Wide→Forced Middle→Forced
Narrow→AUTO. The initial status is AUTO and the display
shows these modes as follows.
•AUTO : A
•Forced Wide : M
•Forced Middle : M
•Forced Narrow : N
• RDS check
PCON is power off when RDS data (“RDS test”) received
for TUNER mode.
5. CD function
• Test mode specifications of the CD receiver
•Each press of the Track Up k e y jumps to the f ollo wing tr ac k
numbers :
No. 9→No. 15→No. 10→No. 11→No. 12→No. 13→No. 22
→No. 14→No. 9 (The cycle restarts from here.)
• Each press of the Track Down key jumps to the previous
track number to the track being played.
•When the number of total tracks of disc is nine or less, unit
playback from a track 1.
• When the media to CD-DA, unit playback from track No. 28
by key operation of preset 1 key.
6. AUDIO function
• Audio-related specifications
•A short press of the Q key initiates the audio adjustment
mode.
• Pressing the OPEN/CLOSE key on the remote controller
initiates the audio adjustment mode.
• Continuous holding of a remote control key is inhibited.
• Bass, Middle and Treble are adjusted in 3 steps of -8 / 0 /
+8 with the Track Up/down keys (default is 0).
• Balance is adjusted in 3 steps of Left L15 / 0 / R15 Max
with the Track Up/down keys (default is 0).
• Loudness : OFF
7. MENU function
• Menu-related specifications
•A short press of the PLAY/PAUSE key initiates the Menu
mode.
• Pressing the DNPP key on the remote initiates the Menu
mode.
• Continuous holding of a remote control key is inhibited.
8. OTHER
• Special display when the display is all on
Pressing the Preset keys while the power is ALL OFF displays the following information.
[PRESET 1] Version display (Month/Day/Hour/Minute)
[PRESET 2] ALL segment light up for FL display
[PRESET 3] Short press : Display CD operation time.
Long press/hold : Clear CD operation time
[PRESET 5] Short press : Display CD ejection count.
Long press/hold : Clear CD ejection count.
[FM] ROM correction version.
If not mounting ROM correction chip set display
shows ROM No___
7
A B C D E
W18
R180
W127
Q
KDC-225/225MR/2025
1
PC BOARD (FOIL SIDE VIEW)
ELECTRIC UNIT X25-9980-11/12/21 (J76-0016-02)
C1
W20
W24
W151
C253
R313
W145
W23
L10
W144
1
D252
D254
W135
W137
W141
W22
W142
P1
2
W152
W241
W240
C254
W138
W136
W19
4
IC11
58
W139
W134
D525
C251
W133
W131
W132
W39
J5
R303
W130
W128
1
W129
BE
R182
W237
L2/W239
Q22
BE
R51
CN2
224
W232
D41
R59
R60
W230
123
D1
W227
W228
W229
12 1
C41
1
42
5
R52
R66
R62
W225
R56
W37
W36
W231
R425
W223
W224
W215
D524
W220
W221
W222
W219
16
1
L1
C25
C26
D26
L12
W218
W226
C202
W33
W216
W217
W35
C20
C22
W34
W32
CC
Q23
W214
W213
L11
D23
EEB
C42
W212
W211
C409
R23
C29
R22
R61
R54
W203
D22
W208
W210
C28
W209
R57
IC8
W207
W206
W31
C33
R58
12
43
C406
C23
C24
W204
W205
D24
R1
W202
R410
D25
C43 C30
W201
D2
D3
D5
W200
W41
R314
R160
R162
9
8
J1
R2
E
B
D526
W198
R53
R63
C410
X1
W196
W191
W195
R3
Q1
R272
W192
W197
W193
R24
W194
R12
R55
60
61
W30
W29
10.0MHz
C201
D255
W187
R31
C31
R32
C3
R4
W177
W188
Q4
EB
2
3
W238
E
Q21
B
C21
Q24
D21
BE
C19
W235
CC
BEE
W40
R21
IC3
4
C27
C45
Q41
IC9
R42
R41
R44
R43
R65
W38
R64
5
6
W234
W236
W233
BE
R407
Q401
D402
W185
D257
D253
W184
R9
R8
C4
R6
R5
BE
Q2
W183
CN5
W28
31
R523
D523
R431
C32
W186
R520
R13
R25
R26
41
IC1
80
R420
C408
D258
D251
D256
TH1
25 1
W182
W181
W180
C5
R33
D31
D4
Q3
BE
R10
R7
R11
R255
D269
D521
R522
D522
BE
C521
Q521
R521
R430
IC6
814
W27
R27
R28
W189
W190
40
21
20
1
C111
R411
R417
R412
R422
C407
R421
R416
R161
X2
32.768kHz
W173
W178
24 2
W174
D271
R252
Q252
C255
BE
R257
C258
R256
C257
R253
R251
R271
R273
W166
W171
C256
D270
W179
C6
W175
17
R315
R432
R312
W160
R207
R210
R209
R208
W170
R154
R152
R153
W172
R415
R419
R413
R418
D201
D202
IC4
W156
W157
W153
W176
W148
W149
W150
W146
W143
DATA
CLK
W158
W159
R106
D156
W168
R254
W147
R206
W167
W164
C252
W165
W169
W161
W25
W140
W155
W162
W163
R181
7
8
2
W134
W241
JIHGF
KDC-225/225MR/2025
1
54
W19
IC11
C251
W133
W131
W132
W39
J2
R307
R304
R305
R303
D301
W17
W16
W130
W121
W123
W126
W128
C211
28 15
1
W18
8
D205
W42
W129
BE
W127
Q151
W124
D401
W122
D162
D157
D158
R171
R180
R174
R182
J5
14
15
576109
1
R310
R311
R309
C303
D308
D309
D307
W120
D203
C210
W14
IC2
C203
C204
R211
C206
W15
D151
D159
R183
R173
R175
1311128432
W115
R308
C301
R301
C302
R306
R302
Q351
Q350
C356
C351
BE
W112
R355
R351
BE
R357
Q352
W106
R358
BE
C352
D310
C504
D502
C502
D503
C503
R506
R505
R502
R504
R503
D311
W119
W118
W117
D501
WH1
61
W113
W9
W109
R105
W8
C507
R508
W111
Q201
W6
C506
W103
W104
W5
C105
L6
W105
L7
L8
W3
CN1
IC10
W2
W100W110
W101
4.332MHz
C209
C205
2
R374
R172
W114
WH2
W12
31
W10
R204
141
C212
R203
R202
R201
R176
BE
R205
W107
C213
W108
W13
R103
W11
1
CN4
W116
91
BE
Q501
R501
J3
R356
R352
Q101
R111
18
169
X3
R507
13
CN6
C104
R101
R102
R104
C106
BE
C108
W1
CN3
12
C115
J4
1
24
R112
L9
R113
C114
C116
IC7
C113 C112
L3
C117
18
169
R114
X25-9980-11/12/21
Ref. No. Address
IC1 6D
IC2 5F
IC3 4B
IC4 2E
IC6 5D
IC8 6C
Q1 3C
Q2 3D
Q3 3D
Q4 5D
Q21 2B
Q22 3B
Q24 3A
Q151 6F
Q201 5G
Q252 3D
Q350 3G
Q351 3G
Q352 3G
Q401 7B
2
3
4
5
6
Refer to the schematic diagram
for the values of resistors and capacitors.
7
9
Loading...