Pioneer PDP-507XD Service Manual page 93

5
Flowchart of Failure Analysis for The Video System
⇒ RGB
Image for the RGB input signal
is not displasyed.
Yes
Is the function correspondeing to
selected signal input selected?
Yes
Which signal is not output,
main or sub signal?
Main
Has the signal arrived at IC4901?
Yes
Is a signal output from IC4901?
(pins 30, 32 and 34)
16 17 18
Yes
Has the signal arrived at IC5101?
(pins 160, 164 and 172)
19 20 21
Yes
Is the communication between
each IC (VDEC, ASIC) on the
MAIN Assy and the microcomputer
normal?
Yes
Replace the MAIN Assy.
Waveforms
Input signal: PAL Color-bar (S terminal)
IC4901 - pin 30
16 17
V: 500 mV/div H: 20 µS/div
IC5101 - pin 160
19 20
V: 500 mV/div H: 20 µS/div
5
6
No
Select the corresponding signal
with the Input selector.
Sub
Is the screen of main side
Analog/Digital TV?
Yes
Has the signal arrived at IC4701?
No
Check the flexible cables between the CN8802 and
No
CN4004 or between CN9003 and CN4005 or around
of input terminals.
Check around IC4901 and check the
No
communications between IC4901
and microcomuputer. If there was
no ploblem, replace the MAIN Assy.
No
Check the circuit between IC4901 and
IC5101 and replace broken parts.
Check around the IC that is found to
No have failure in communication and
the microcomputer. If there was no
ploblem, replace the MAIN Assy.
IC4901 - pin 32 IC4901 - pin 34
18
V: 500 mV/div H: 20 µS/div V: 500 mV/div H: 20 µS/div
IC5101 - pin 164 IC5101 - pin 172
21
V: 500 mV/div H: 20 µS/div V: 500 mV/div H: 20 µS/div
6
7
No
Specifications that does not
display in the sub-side.
Yes
No
Replace the FFCs or cables.
Is a signal output from
12 13
IC4701? (pins 47 and 49)
Yes
Has the signal arrived at
14 15
IC5103? (pins 1 and 2)
Yes
PDP-507XD
7
8
Check around IC4701 and check the
No
communications between IC4701
and microcomuputer. If there was
no ploblem, replace the MAIN Assy.
Check the emitter-follower circuit
No
between IC4701 and IC5103 and
repair the failure points.
8
A
B
C
D
E
F
93