3-13
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Only for training and service purposes.
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the USB FUNCTION, repair the set according to the following guide.
5-3. IN THE USB FUNCTION
5-3-1. Solution
Please check and replace IC500 and IC104 on MAIN board.
5-3-2. How to troubleshoot (Countermeasure)
1) Check +USB_5V to Front USB board.
2) Check USB D1± or USB D2± from MAIN board to Front USB board.
a. Check 2.0_D1±signals(pin U7, U8 ) or 1.1_D1± signals(pin A7, A8 ) to IC500.
b. Check USB± signals to CN502(pin1, 2, 4, 5).
3) If there is any trouble, check the power for each IC. The power is normal but , if the signal waveform to
the IC is distorted or no signal, replace it with a new one.
5-3-3. Service hint (Any picture / Remark)
D- to pin 1&4 of CN502
D+ to pin 2&5 of CN502
< Waveform of USB D± signal >
< USB function signal
fl
ow >
II C501
Mai n DSP
( +3. 3V_CD, VCC1. 2)
DECK
MECHANI SM
M
P/ UP
( VCC50)
I C400
Mot or Dr i ve
SERVO
I C401
( 4 X)
OP_SW,CL_SW,UP_SW,DN_SW,D_SENSE
MOT_MUTE, CLOSE, OPEN
A, B, C, D, E, F, PD
LD
SPDO/ SLDO
/ FOD/ TRD
LOAD± , SLED± ,
SPI N± , TR± , F±
P
W
M
_
L
R
C
K
/
B
C
K
/
D
A
T
A
CD_RW/MCLK/ LRCK/ BCK,
CD_DAT
CD_RST
MD
Bl ock
FRONT( BTL)
SW(PBTL)
[CK57 : Total 2.1ch 1100W
350+350+400]
[CK56 : Total 2ch 700W]
LPF
AMP
I c701
PW
M
I C700
FRONT( BTL)
PWM + AMP Bl ock
AMP
I C702
CK57 Only
LPF
USB1
USB2
D2S+/ -
1. 1
2. 0
D1+/ -