11
DDJ-RB
5
6
7
8
5
6
7
8
A
B
C
D
E
F
5.2 TROUBLESHOOTING
In this section, causes of failure, diagnostics points, and corrective measures can be searched for according to symptoms.
For the relationship of each power-supply and signal system, see “4.3 POWER BLOCK DIAGRAM.”
If software of the product is updated before performing diagnostics, check that software updating has been performed properly
before proceeding to diagnostics.
If software updating has not been performed properly, update the software, following the instructions in
“8.2 UPDATING OF THE FIRMWARE.”
The waveform numbers and voltage confirmation-point numbers described in this section correspond to the numbers on the
circuit diagrams and PCB diagrams.
Be sure to check the failure points, as well as check for failure in their peripheral circuits.
1
Failure in the
power system (1)
MAIN Assy
Check that the voltage of the direct pin of
USB jack (JA101) is in the range of
4.75–5.25 V.
If the voltage is outside the range of 4.75–5.25 V,
failure in the USB-bus power, USB cable and
USB jack (JA101).
4.3 POWER BLOCK
DIAGRAM
5.3 MONITORING
OF POWER SUPPLY
AND VOLTAGE
2
Failure in USB-
bus power
MAIN Assy
Check that the V+VBUS voltage is lower
than that of the direct pin of USB jack
(JA101) by approximately 0.1 to 0.2 V.
If the voltage is 0 V, the wire for the IC protector
(P101) may be broken.
4.3 POWER BLOCK
DIAGRAM
3
Power failure in
the UCOM
MAIN Assy
If V+3R3_SH is abnormal
(2.7 V or less)
If the normal voltage of V+3R3_SH is not restored,
IC202 or a part that is connected to V+3R3_SH on
the MAIN Assy may be defective, or connection may be poor.
4.3 POWER BLOCK
DIAGRAM
In a case where the unit is not started after the USB cable is connected and the unit is turned ON (all LED are not lit)
4
Power failure in
the UCOM
MAIN Assy
If the V+3R3_SH voltage is normal,
check that Q203 (5V FET SW) is
functioning properly.
If the PWR_ON signal is "L," V+5D, V+5_LED will not
be output, because Q203 is not turned ON.
The error-detection circuit may have been activated.
Go to [5].
If the PWR_ON signal is "H," the error-detection
circuit is not activated. Check the voltages of all
power ICs. If they are normal, see "[1-2] Failure in
the microcomputer system."
4.3 POWER BLOCK
DIAGRAM
1
———
Service mode
Identify a failure point.
After a failure point is identified, see the section
referenced in this manual.
6. SERVICE MODE
1
Disconnection,
breakage, or
loose connection
of internal cables
Cables
Check that all the cables are securely
connected. Check that there is no
breakage in the cables.
Securely connect a cable if it is not connected.
If a cable is broken, replace it.
Note:
If an FFC cable is disconnected, be careful of
the orientation of the contacts when reconnecting it,
referring to the printed guide on the board.
4.1 OVERALL
WIRING DIAGRAM
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
[0] Prior Confirmation
[0-1] Checking in Service Mode
[0] Prior Confirmation
[1] Failure in Startup (Failure in power-on)
[2] Display (LED indicators)
[3] Operations (Buttons / Volumes / Faders / Sliders / Jog dial
[4] USB connection
[5] AUDIO OUT
[6] AUDIO IN
[7] Basic Operation Check of the MAIN UCOM
[0-2] Checking Internal Cables
Contents
[1] Failure in Startup (Failure in power-on)
[1-1] Failure in the power system
