Pioneer PDP-4271HD Service Manual page 93

5
Flowchart of Failure Analysis for The Audio System
No sound from panel
⇒ AU1
Has the sound been emitted from
the speakers?
Yes
Has the sound of the digital channel
broadcasting (ANT-A) output?
Yes
Has the sound of the Analog channel
broadcasting (ANT-A,B) output?
Yes
a
5
6
No
Is sound muting set?
No
Is the volume set to 0?
No
Is a picture displayed?
Yes
Is a signal output from IC6301and
come to CN4007?
Yes
Is a signal come to AUDIO Assy?
Yes
Is a sound output from
AUDIO Assy?
Yes
Check the speakers and speaker
cables.
No
Is a signal input to IC4401?
(pin 1, 8)
Yes
Is a signal input to IC4402?
(pin 21)
Yes
Is a signal output from IC4402?
(pin 29, 30)
Yes
Is a signal input to IC4701?
(pin 19, 20)
Yes
Is a signal output from IC4701?
(pin 35, 36)
Yes
Is a signal output from IC7102?
(pin 1, 7)
Yes
Is a signal come to IC7101?
(pin 1, 2)
Yes
Is a signal come to IC6301?
Yes
Is a signal output from IC6301 and
come to CN4007? (pin 3, 5)
Yes
b
6
7
Yes
Cansel muting then check again.
Yes
Raise the volume then check again.
No
Check digital channel broadcasting.
No
Check the communication
between CN4007 and IC6301.
No
Check the cables and connector
between MAIN and AUDIO Assys.
If it's no problem, replace audio
signal cable.
No
Check the communication
between AUDIO Assy and the
microcomputer. If it's no problem,
replace AUDIO Assy.
No
Check the communications around
the FE (U4401 or U4402) and
between the FE (U4401 or U4402)
and the microcomputer.
No
Check around IC4402 and check
the communications between
33
IC4402 and the FE.
No
Check the communications around
the IC4402 and between the IC4402
34
and the microcomputer. If there was
no ploblem replace IC4402.
No
Check the communication
between IC4402 and IC4701.
35
No
Check around IC4701 and check
the communications between
36
IC4701 and the microcomputer.
No
Check the communication
between IC4701 and IC7102.
Check arround IC7102.
No
Check the communication between
IC7102 and IC7101. If there was
37
no ploblem replace IC7102.
No
Check the communication between
IC6301and IC7101. If there is no
problem, replace IC7101.
No
Check the communication between
CN4007 and IC6301. If there is no
38
problem, replace IC6301.
PDP-4271HD
7
8
NG
Replace the MAIN Assy.
NG
Replace the MAIN Assy.
NG
Replace the MAIN Assy.
NG
Replace the MAIN Assy.
NG
Replace the MAIN Assy.
NG
Replace the MAIN Assy.
NG
Replace the MAIN Assy.
8
A
B
C
D
E
F
c
93