PDP-427XD
87
5
6
7
8
5
6
7
8
C
D
F
A
B
E
Is the function corresponding to
selected signal input selected?
Select the corresponding signal
with the input selector.
No
Replace the flexible cable.
No
Check the flexible cables between the CN8802
and CN4004 or between CN9003 and CN4005
or around of pin jack.
No
Check the circuit between IC4901 and IC5301.
If there was no ploblem, replace the MAIN Assy.
No
Check around IC4901 and check the communications
between IC4901 and the microcomputer.
If there was no ploblem, replace the MAIN Assy.
No
Check around the IC that is found to have a failure
in communication and the microcomputer.
If there was no ploblem, replace the MAIN Assy.
No
Replace the MAIN Assy.
Yes
Yes
Image for the component signal
is not displayed.
⇒
COMP/PC1
Has the signal arrived at IC4901 ?
(pins 2, 4, 6)
Yes
Which signal is not output,
main or sub signal?
Is a signal output from IC4901?
(pins 41, 43, 45)
Has the signal arrived at IC5301?
(pins 43, 48, 54)
Yes
Yes
Is the communication between
each IC (VDEC, ASIC) on the
MAIN Assy and the microcomputer
nomal?
Yes
Yes
Sub
Main
24
23
22
27
26
25
30
29
28
22
IC4901 - pin 2
V: 500 mV/div H: 10
µ
S/div
23
IC4901 - pin 4
V: 500 mV/div H: 10
µ
S/div
27
IC4901 - pin 45
V: 500 mV/div H: 10
µ
S/div
28
IC5301 - pin 43
V: 500 mV/div H: 10
µ
S/div
Waveforms
Input signal: Color-bar (Component 1080i)
24
IC4901 - pin 6
V: 500 mV/div H: 10
µ
S/div
29
IC5301 - pin 48
V: 500 mV/div H: 10
µ
S/div
25
30
IC4901 - pin 41
V: 500 mV/div H: 10
µ
S/div
IC5301 - pin 54
V: 500 mV/div H: 10
µ
S/div
26
IC4901 - pin 43
V: 500 mV/div H: 10
µ
S/div
No video from component
Flowchart of Failure Analysis for The Video System
Is the screen of main side
Analog/Digital TV?
No
Specifications that does not
display in the sub-side.