Pioneer SC-LX90 Service Manual page 93

1
A
B
Confirmation of symptoms
• Is there a log that indicates detection of an
abnormality?
C
Confirmation of connections
Yes
• In normal display mode, is the indication for
the external input displayed on the LCD when
the LCD or VIEW key is pressed?
D
If an overload is detected,
are the cables connected
with the SP terminals short-
circuited?
Yes
Connect the Failure in the
cables properly location where
the overload was
E
detected
Failure in communications (connections) between a
microcomputer whose version is not displayed and the
system (main) microcomputer (For details on the Assys
on which microcomputers are mounted, see the block
diagram.)
* If the version of the AUDIO (DSP) microcomputer is not
displayed, check also the connection between the DSP
F
Assy and the MAIN DIGITAL Assy.
38
1
2
Determination of whether the display system or
other system is in failure
• Is the normal screen displayed?
OK
No
Abnormality in the HDMI microcomputer
OK
or poor connection
No
Confirmation of connections
• Are the versions for all the microcomputers, etc. displayed?
NG
2
3
B
OK
Determination of whether the power supply system
or the microcomputer system is in failure
1 Does the MCACC indicator light?
2 Does the 10-ch indicator or LCD backlight light?
Only 2 unavailable
Failure in 8-V power
supply or poor
OK
connection
NG
Failure in the Assy that cannot be controlled or poor
connection between the uncontrollable Assy and
other Assy
SC-09TX
3
4
NG
Neither 1 nor 2
available
Failure in the
DISPLAY
microcomputer
OK
4