Casio CDP-120 Troubleshooting guide

CDP-120
Ver. 1 : Dec. 2012
CDP-120
JUL. 2011
ELECTRONIC KEYBOARD

CDP-120
CONTENTS
SPECIFICATIONS........................................................................................... 1
BLOCK AND WIRING DIAGRAM .................................................................. 2
PCB INFORMATION....................................................................................... 3
CIRCUIT DESCRIPTION ................................................................................ 4
PRINTED CIRCUIT BOARDS......................................................................... 6
DISASSEMBLY............................................................................................... 9
DIAGNOSTIC PROGRAM ............................................................................ 25
EXPLODED VIEW......................................................................................... 28
PARTS LIST.................................................................................................. 30
SCHEMATIC DIAGRAMS............................................................................. 33

CDP-120
– 1 –
SPECIFICATIONS
Keyboard 88-key piano keyboard
Touch Response 3 types, Off
Maximum Polyphony 48 notes (24 for certain tones)
Tones
Built-in Tones 5; with layer
Reverb 1 to 10, Off
Chorus 1 to 5, Off
Demo Songs 5 songs (tone demo songs)
Other Functions
Transpose ±1 octaves (-12 to +12 semitones)
Tuning A4 = 415.5 to 465.9 Hz (Initial Default: 440.0 Hz)
MIDI 16 multi-timbre received, GM Level 1 standard
Inputs/Outputs
USB port TYPE B
Damper Pedal jack Standard jack
Phones/Output jack Stereo standard jack
Output Impedance: 3 Ω, Output Voltage: 1.5 V (RMS) MAX
Power Jack 12 V DC
Power Supply
AC Adaptor AD-A12150LW
Auto Power Off 30 minutes after last key operation, Auto Power Off can be disabled.
Speakers (12 cm × 6 cm oval) × 2
Output 8 W + 8 W
Power Consumption 12 V 18 W
Dimensions 132.2 × 28.6 × 12.9 cm (52 1/16 × 11 1/4× 5 1/16 inch)
Weight Approximately 11.4 kg (25.1 lbs)

CDP-120
– 2 –
BLOCK AND WIRING DIAGRAM
KEYBOARD PCB
(M914-KYA1)
MAIN PCB
(M914-MDA1)
POWER AMP PCB (M914-PSA1)
KEYBOARD PCB
(M914-KYB1)
KEYBOARD PCB
(M914-KYC1)
POWER SWITCH
(SW1)
DC 12 V (J3)
CN802 (16 pin) CN804 (16 pin) CN805 (16 pin)
CN803 (30 pin)
CN14 (30 pin)
CN11 (11 pin)
CN3 (11 pin)
CN2 (2 pin)
CN1 (2 pin)
CN20 (5 pin)
CN4 (5 pin)
USB
PHONES (J2)
PEDAL (J5)
SPEAKER (L)
SPEAKER (R)
MAIN VOL. (VR1)
CN19 (4 pin)
CN801 (16 pin)
FI0~FI10,
SI0~SI10,
KC0~KC7
LOUT, ROUT
KI0~KI2, KC0, KC1
PEDAL,
APO, POFF,
MUTE, MIC IN
MPU
IC7
Headphones
Amplifier
IC1
Power
Amplifier
IC2
MA1~MA22
MD0~MD15
Flash Memory
(64 Mbit)
IC2
Filter
IC5
Power Supply Circuit
IC6, C24, C25,
C27, C33, C35
VD3
VCP
Power
Supply Circuit
IC3, Q4, D1
Power Supply Circuit
IC3, Q4, D1,
C40~C45
VA5 VD5
VD5VA5
LOUT
ROUT
D2
BUTTONS

CDP-120
– 3 –
PCB INFORMATION
M914-MDA1M914-PSA1
M914-KYA1 M914-KYB1 M914-KYC1
Classifi cation Parts Name PCB Name Components
Main PCB PCB UNIT/MAIN M914-MDA1 MPU, Flash Memory (64 Mbit),
Power Supply Circuit, Filter, USB Port
Power Amp PCB PCB UNIT/PSA1 M914-PSA1
Power Supply Circuit, Power Ampli er
Headphones Ampli er, Power Switch,
Main Volume, DC 12 V Terminal,
DAMPER PEDAL Jack,
PHONES/OUTPUT Jack, Buttons
Keyboard PCB PCB UNIT/KY and
RUBBER CONTACT
M914-KYA1
KeyboardM914-KYB1
M914-KYC1

CDP-120
– 4 –
CIRCUIT DESCRIPTION
 KEY MATRIX
KC0 KC1 KC2 KC3 KC4 KC5 KC6 KC7
FI0 A01A0#1B01C11C1#1D11D1#1E11
SI0 A02A0#2B02C12C1#2D12D1#2E12
FI1 F11F1#1G11G1#1A11A1#1B11C21
SI1 F12F1#2G12G1#2A12A1#2B12C22
FI2 C2#1D21D2#1E21F21F2#1G21G2#1
SI2 C2#2D22D2#2E22F22F2#2G22G2#2
FI3 A21A2#1B21C31C3#1D31D3#1E31
SI3 A22A2#2B22C32C3#2D32D3#2E32
FI4 F31F3#1G31G3#1A31A3#1B31C41
SI4 F32F3#2G32G3#2A32A3#2B32C42
FI5 C4#1D41D4#1E41F41F4#1G41G4#1
SI5 C4#2D42D4#2E42F42F4#2G42G4#2
FI6 A41A4#1B41C51C5#1D51D5#1E51
SI6 A42A4#2B42C52C5#2D52D5#2E52
FI7 F51F5#1G51G5#1A51A5#1B51C61
SI7 F52F5#2G52G5#2A52A5#2B52C62
FI8 C6#1D61D6#1E61F61F6#1G61G6#1
SI8 C6#2D62D6#2E62F62F6#2G62G6#2
FI9 A61A6#1B61C71C7#1D71D7#1E71
SI9 A62A6#2B62C72C7#2D72D7#2E72
FI10 F71F7#1G71G7#1A71A7#1B71C81
SI10 F72F7#2G72G7#2A72A7#2B72C82
Each key has two contacts, the rst contact 1and second contact 2.
NOTE: The diagram below illustrates how the contacts work.
Key
Second contact First contact 
FI
KC
SI

CDP-120
– 5 –
 NOMENCLATURE OF KEYS
F#3G#3 A#3 C#4D#4 F#4G#4A#4 C#5D#5 F#5G#5 A#5
F3 G3 A3 B3 C4 D4 E4 F4 G4 A4 B4 C5 D5 E5 F5 G5 A5 B5 C6
D#3
C2 D2 E2 F2 G2 A2 B2 C3 D3 E3 B6A6G6F6E6D6 C7
C#3A#2G#2F#2D#2C#2
C1 D1 E1 F1 G1 A1 B1A0 B0
A#1A#0 G#1F#1D#1C#1 A#6G#6F#6D#6C#6
B7A7G7F7E7D7 C8
A#7G#7F#7D#7C#7
 BUTTON MATRIX
SWO0 SWO1
SWI3 STRINGS GRAND PIANO 2
SWI4 GRAND PIANO 1 HARPSICHORD
SWI5 DEMO, FUNCTION ELEC PIANO

CDP-120
– 6 –
PRINTED CIRCUIT BOARDS
Main PCB: M914-MDA1 Power Amp PCB: M914-PSA1

CDP-120
– 7 –
Keyboard PCB: M914-KYA1
Keyboard PCB: M914-KYB1

CDP-120
– 8 –
Keyboard PCB: M914-KYC1

CDP-120
– 9 –
DISASSEMBLY
 CAUTION
z The photos show a prototype. The appearance of the instrument, such as color, may
differ from the actual model.
z To avoid damages to the instrument and the oor, lay the instrument on a mattress
or blanket before starting disassembling.
z There are several kinds of screws. Be sure to use the correct type of screws when
reassembling. It is advisable to sort the screws as shown below after removing
them.
z If a screw cap is attached to a screw, be sure to reattach the screw cap when
reassembling.
 BEFORE STARTING REPAIR OR SERVICING
z Remove the AC adaptor, AC cord or batteries.
z Remove accessories such as the music stand.

CDP-120
– 10 –
 DISASSEMBLY
A. REMOVE THE PANEL UNITS
Main panel unit Right panel unitLeft panel unit
A-1. Undo 10 or six screws on the bottom surface of the main unit.
NOTE: To remove only the main panel unit, undo six screws indicated with red circles in the
illustration below.
A-2. Undo eight or four screws and then remove eight or four LOWER-COVERs.
NOTE: To remove only the main panel unit, undo four screws and remove the four LOWER-
COVERs indicated with red circles in the illustration below.
A-3. You will see a screw inside when you remove an LOWER-COVER. Undo and remove the screw
through each opening (eight or four screws in total).
NOTE: Do not drop the screws inside the main unit.
NOTE: Do not touch the hammer with the screwdriver while loosening the screws.
LOWER-COVER

CDP-120
– 11 –
A-4. Place the main unit with the keys facing up.
A-5. Lift the main panel unit and turn it over.
NOTE: The main panel unit is connected to the lower case unit with the connectors and FFC.
Use caution when turn over the main panel unit.
A-6. Release the connector lock and remove the FFC.
A-7. Remove two connectors and then remove the main panel unit.
Main panel unit
Connector
(Right speaker)
FFC
(M914-KYB1)
Connector
(Left speaker)

CDP-120
– 12 –
A-8. Undo three screws on the RIGHT-SIDE-CASE and then remove the RIGHT-SIDE-CASE.
RIGHT-SIDE-CASE
A-9. Undo three screws on the LEFT-SIDE-CASE and then remove the LEFT-SIDE-CASE.
LEFT-SIDE-CASE

CDP-120
– 13 –
A-10. Undo two screws on the RIGHT-SIDE-INNER-CASE and then remove the right panel unit.
RIGHT-SIDE-INNER-CASE
Right panel unit
A-11. Undo two screws on the LEFT-SIDE-INNER-CASE and then remove the left panel unit.
LEFT-SIDE-INNER-CASE
Left panel unit

CDP-120
– 14 –
B. REMOVE THE M914-MDA1 PCB (MAIN PCB)
B-1. Remove two connectors.
B-2. Undo four screws and then remove the M914-MDA1 PCB.
M914-MDA1 PCB Connectors (M914-PSA1)
C. REMOVE THE M914-PSA1 PCB (POWER AMP PCB)
C-1. Remove the ROTARY-KNOB
ROTARY-KNOB
C-2. Remove two connectors from the M914-MDA1 PCB.
M914-MDA1 PCB M914-PSA1 PCBConnectors (M914-PSA1)
C-3. Undo 11 screws and then remove the M914-PSA1 PCB and rubber key.
M914-PSA1 PCB M914-PSA1 PCB

CDP-120
– 15 –
D. REMOVE THE SPEAKER
D-1. Unsolder two lead wires.
D-2. Undo four screws and then remove the SPEAKER.
<Left speaker> <Right speaker>
Lead wire (Black)
Lead wire (Red)
Lead wire (Red)
Lead wire (Black)
E. REMOVE THE KY-ASSY
E-1. Undo three screws and then remove the LEFT-SIDE-INNER-CASE.
LEFT-SIDE-INNER-CASE
E-2. Undo three screws and then remove the RIGHT-SIDE-INNER-CASE.
RIGHT-SIDE-INNER-CASE
E-3. Undo 26 screws.

CDP-120
– 16 –
E-4. Undo three screws and then remove the KY-ASSY.
KY-ASSY
LOWER-CASE-UNIT

CDP-120
– 17 –
 DISASSEMBLY OF THE KY-ASSY
A. REMOVE THE KEYS
<Removing the keys>
• To remove the keys, you will need two of the tools described below.
• Before removing a black key, you must rst remove both white keys on either side of the black
key.
• White keys may be removed with the same procedures as removing black keys.
<Tool>
The tool used in the photos in this section was converted from a gardening ID tag. The size and
shape of an ID tag accord to the dimensions below.
<Note on shaping an ID tag>
The thickness of the tool must be within 1.2~1.3 mm. If the tool is too thin, removing keys become
difcult. If the tool is too thick, it may damage the rib of the chassis.
<Tool dimensions>
Width:
15~20 mm R=2.75 mm
Use this part to
remove the key.
7 mm
Thickness:
within 1.2~1.3 mm

CDP-120
– 18 –
A-1. Insert the two tools between the rib of the chassis and a key.
A-2. When the tools are inserted to a certain depth, the key begins to be lifted and can then be
removed.
<Cross-section image>
Tools
Chassis
Tool
Key
Rib of the chassis