Pioneer PDP-5050SX Service Manual page 143

5
Image for the composite or S signal is not displayed
If no picture is displayed, press the POWER button to turn the power off then back on after a while.
When the red LED is flashing, the power has been Power down. Check how many times the LED is flashing.
(See the Power-down diagnosis on page 134.)
When the green LED is lit, follow the procedures below:
Image for the composite or
S signal is not displayed
No
Is the function corresponding
No Select the corresponding
to selected signal input
selected?
Yes
Has the signal arrived at
No
IC8002?
Yes
Which signal is not output, Subsignal
main or subsignal?
Main signal
Is a signal output from
No
IC8002?
3 4
(44) (47)
Yes
Has the signal arrived at
No
IC6107?
7 8
(52) (59)
Yes
Is the communication
No
between each IC on the
MAIN BOARD Assy and
the microcomputer normal?
Yes
Has the symptom been
No
settled when the MAIN
BOARD Assy is replaced?
Yes
Finishing troubleshooting
5
6
signal with the Input selector.
Check the communication
between the jack and
IC8002.
Check around IC8002 and
check the communications
between IC8002 and the
microcomputer.
Check the communications
between IC8002 and
IC6107.
Check around the IC that is
found to have a failure in
communication and the
microcomputer.
The panel is defective.
PDP-5050SX
6
7
TV signal is not displayed
on the screen.
Yes
Is the Input selector set to
TV?
Yes
Is a signal output normally
from the FE
1
(U7501)? (18)
Yes
Has the signal arrived at
IC8002?
2
(63)
Yes
Is a signal output from
No
IC8002?
5 6
(56) (58)
Yes
Has the signal arrived at
IC6255?
9 10
(52) (59)
Yes
Note:
• Diagnosis points
MAIN BOARD ASSY
AV BOARD ASSY
• For check the communication with the microcomputer,
refer to the section 6.5 SERVICE FACTORY MODE.
• The encircled numbers denote measuring point in the
Waveforms for Troubleshooting.
7
8
No
Set the Input selector to TV.
Check around the FE and
No
check the communications
between the FE and the
microcomputer.
Check the communications
No
between U7501 and
IC8002.
Check the communications
No
between IC8002 and
IC6255.
8
A
B
C
D
E
F
143