Pioneer CDJ-900 Service Manual page 29

5
Other LED does not light.
No. Cause Diagnostics Point
Breakage
1 Related point
of protectors
2 Signal errors -
Defective parts
3 -
of LED
Defective parts
4 -
of transistor
[3] Operations (Keys/variable controls/JOG)
As operations of all keys, variable controls, and JOG dial can be checked in Service mode.
[3-1] No key functions
The PLAY, CUE, AUTO BEAT LOOP, BEAT SELECT, REV, LOOP IN, LOOP OUT, or RELOOP key does not function.
No. Cause Diagnostics Point
Loose connection
1 Related point
/Defective SW
Defective PANEL
2
DFLB Assy
CPU (IC8005)
Other keys (except for the USB STOP key) do not function.
The signals from other keys are analog and connected to multiple switches.
No. Cause Diagnostics Point
Loose connection
1 Related point
/Defective SW
Defective PANEL
2 DFLB Assy
CPU (IC8005)
The USB STOP key does not function.
The USB STOP key is controlled by the MAIN CPU.
No. Cause Diagnostics Point
KSWB Assy/
Loose connection
1
MAIN Assy
/Defective SW
Defective MAIN
2 MAIN Assy
CPU (IC101)
[3-2] Rotary selector not controllable
No. Cause Diagnostics Point
Defective rotary
1 ENCB Assy
selector
Defective PANEL
2 DFLB Assy
CPU (IC8005)
[3-3] Variable controls not controllable
Tempo slider not controllable
No. Cause Diagnostics Point
Loose
SLDB Assy
1
connection
/DFLB Assy
Defective tempo
2 SLDB Assy
slider
Defective PANEL
3 DFLB Assy
CPU (IC8005)
5
6
Item to be Checked
Check the drive voltage of the unlit LED.
For the 5-V-driven LEDs, check if the
protector (P3) is broken.
Check that the signal for the LED in
question is output from the PANEL CPU
(IC8005).
Check that the forward voltage (2.2 - 2.7 V)
is present at both ends of the LED.
If the symptom persists after the above
corrections,
Item to be Checked
Check if there is loose connection on the
signal line from the PANEL CPU (IC8005)
up to the SW.
If the symptom persists after the above
corrections,
Item to be Checked
Check if there is loose connection on the
signal line from the PANEL CPU (IC8005)
up to the SW.
If the symptom persists after the above
corrections,
Item to be Checked
Check if there is loose connection on the
signal line from the MAIN CPU (IC101)
up to the SW.
If the symptom persists after the above
corrections,
Item to be Checked
Check if the signals from the ENC_1, ENC_2,
and ENC_SW signal lines are normal when
the rotary selector is turned or pressed.
If the symptom persists after the above
corrections,
Item to be Checked
Check if there is loose connection on the
signal line from the PANEL CPU (IC8005)
to the tempo slider (VR8701).
Check the waveforms of signal lines
(ADCT/ADIN) .
If the symptom persists after the above
corrections,
CDJ-900
6
7
Corrective Action
If the protector is broken, replace the protector.
When there is not output signal, check the connec-
tion of the PANEL CPU (IC8005). If the connection
is OK, the port may be damaged. Replace it.
If the forward voltage is not present, then the LED
itself is defective. Replace it.
The transistor is defective. Replace it.
Corrective Action
If there is no loose connection and if the signal does
not become L when the SW is pressed, that SW is
defective. Replace it.
Check the connection of the PANEL CPU (IC8005).
If the connection is OK, the port may be damaged.
Replace it.
Corrective Action
If the SWs connected to the signal line function
properly and if the connections are properly made,
the SWs may be defective. Replace them.
Check the connection of the PANEL CPU (IC8005).
If the connection is OK, the port may be damaged.
Replace it.
Corrective Action
If there is no loose connection and if the signal does
not become L when the SW is pressed, that SW is
defective. Replace it.
The MAIN CPU (IC101) is defective. Replace it.
Corrective Action
If the signals are not normal, check the connections of
the signal lines. If the connections are properly made,
the encoder selector may be defective. Replace it.
Check a mounting state of PANEL CPU(IC8005).
If the mounting is OK, the PANEL CPU is damaged.
Replace it.
Corrective Action
If the connections of signal line are improper,
resolder it.
If the voltage of the signal line (ADIN) does not
change between 3.3 V and 0 V, the tempo slider
(VR8701) may be defective. Replace it.
Check a mounting state of PANEL CPU(IC8005).
If the mounting is OK, the port may be damaged.
Replace it.
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8
A
Reference
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- B
Reference
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C
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Reference
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D
Reference
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Reference
10.7 DFLB and
ENCB ASSYS
E
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Reference
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F
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