PDP-427XD
79
5
6
7
8
5
6
7
8
C
D
F
A
B
E
No
Is the waveform normal when the
voltage is applied to the panel?
(See the oscilloscope photos.)
Are all the connectors properly
connected?
Reconnect the connectors.
No
Set the VH voltage correctly.
X DRIVE Assy
Y DRIVE Assy / SCAN A, B Assy
ADDRESS Assy
Abnormality across the whole
screen, such as luminescent spots
B
D
C
NG
Yes
No
Set the VOFS voltage correctly.
NG
Is the VH set voltage (130 V)
correctly set?
Yes
Is the VOFS set voltage correctly
set (set value: designated for
each panel)?
No
No
Another Assy may be in failure.
Set the VYRST voltage correctly.
No
Replace the FFC cables.
Replace the DIGITAL Assy.
Replace the Y DRIVE Assy.
Replace the SCAN IC.
NG
NG
NG
Yes
Yes
Yes
Yes
Yes
Is the VYRST set voltage correctly
set (set value: designated for
each panel)?
Is the input signal normal?
(See the oscilloscope photos.)
No
Is the waveform of the control
signal from the SCAN Assy
normal?
(See the oscilloscope photos.)
Failure analysis for the
drive system
⇒
DR2
Because it is difficult to identify which drive is in failure, follow the flowchart below to check each Assy.
Flowchart of Failure Analysis for The Drive Assy