22
DJM-850-K
1
2
3
4
A
B
C
D
E
F
1
2
3
4
1-12
3
24MCLK
error
MAI
N
Assy
R3234
Check for the 24M_CLK_DSP signal.
• If an output signal can be confirmed, go to [4].
• If an output signal cannot be confirmed, the
24MCLK (IC3204) block may be defective.
Check for the status of soldering and replace it.
10.35
W
A
V
EFORMS
3
24MCLK
error
MAI
N
Assy
R2624
Check for the 24M_CLK signal.
This is a simple check of whether a signal
is output or not. A normal waveform
cannot be observed, because the drive
circuit is inside the IC.
• If an output signal can be confirmed, go to [4].
• If an output signal cannot be confirmed, the
crystal (X2601) block or USB UCOM (IC2603)
may be defective.
Check for the status of soldering and replace it.
10.35
W
A
V
EFORMS
1-12
1-13
1-14
1-15
4
Defective parts
MAI
N
Assy
IC3201
IC300
8
If the symptom persists after the above
corrections.
DSP (IC3201) or FLASH (IC300
8
) may be
defective.
Check for the status of soldering and replace it.
—————
4
Defective parts
MAI
N
Assy
IC2603
IC2
8
02
If the symptom persists after the above
corrections.
USB UCOM (IC2603) or FLASH (IC2
8
02)
may be defective. Replace it.
—————
[1-5] The unit dose not turn on, and the LED of the SETUP LED flashes once.
1
Power failure,
defective parts
MAI
N
Assy
R3209
F3201
• Check for the
V
+3R3D_DSP power.
• Check for the
V
+1R2D_DSP power.
• If the
V
+3R3D_DSP power and
V
+1R2D_DSP power can be confirmed,
go to [2].
• If either power cannot be confirmed, the power
line may be defective.
Check for the status of soldering and replace it.
4.4 PO
W
ER
BLOCK DIAGRAM
5.3 I
N
FORMATIO
N
O
N
PO
W
ER
DIAG
N
OSTICS
Communication error between the MAI
N
UCOM (IC2
8
03) and DSP (IC3201).
[1-6] The unit dose not turn on, and the LED of the SETUP LED flashes six times.
1
Power failure,
defective parts
MAI
N
Assy
R2604
F2601
R2611
• Check for the
V
+3R3D_USB power.
• Check for the
V
+1R2D_USB power.
• Check for the
V
+2R5D_USB_PLL
power.
• If the all power can be confirmed, go to [2].
• If either power cannot be confirmed, the power
line may be defective.
Check for the status of soldering and replace it.
4.4 PO
W
ER
BLOCK DIAGRAM
5.3 I
N
FORMATIO
N
O
N
PO
W
ER
DIAG
N
OSTICS
Communication error between the MAI
N
UCOM (IC2
8
03) and USB UCOM (IC2603)
[1-7] The unit dose not turn on, and the LED of the SETUP LED flashes endlessly.
1
Power failure
See “5.4
V
OLTAGE
MO
N
ITORI
N
G
CIRCUIT.”
Check for power at each point, following
“5.4
V
OLTAGE MO
N
ITORI
N
G CIRCUIT.”
Repair the defective parts.
5.4
V
OLTAGE
MO
N
ITORI
N
G
CIRCUIT
The unit is shut down in error by the
V
oltage Monitoring Circuit.
1-9
1-10
2
RESET signal
error
MAI
N
Assy
R3276
Check that the signal level of
DSP_RESET is High.
• If the signal level is High, go to [3].
• If the signal level is low, something on the
DSP_RESET path may be wrong.
Check for the status of soldering and replace it.
—————
1-11
2
RESET signal
error
MAI
N
Assy
R2669
Check that the signal level of
USB_RESET is High.
• If the signal level is High, go to [3].
• If the signal level is low, something on the
USB_RESET path may be wrong.
Check for the status of soldering and replace it.
—————
1-16
1-17
1-17
No.
Cause
Diagnostics Point
Item to be Checked
Corrective Action
Reference
No.
Cause
Diagnostics Point
Item to be Checked
Corrective Action
Reference
No.
Cause
Diagnostics Point
Item to be Checked
Corrective Action
Reference
