Pioneer PDP-42MXE20, Service Manual, Page: 35 / 120

PDP-427CMX
35
5 6 7 8
5 6
7
8
C
D
F
A
B
E
Abnormality in audio (no sound from the speaker)
NO
NO
NO
NO
YES
YES
With the speaker cables disconnected,
are audio signals output from the
speaker terminals?
Is the green POWER indicator repeating a
burst of 5 flashes?
Is an audio signal input of the video slot to
the main unit NOT output although an
audio signal input to AUDIO 1 or 2 is
output?
Is either of the audio signals input to
AUDIO INPUT 1 or 2 of the monitor
output when selected?
Failure in the speakers or speaker cables
NO
Is the video slot card properly
installed? Install the video slot card
properly.
YES
Failure in the MAIN PWB
or the CN3004 (AU connector) cable
Failure in the IC5308 or the poor
connection of the AUDIO input
terminal
Failure in the MAIN PWB
or the CN3004 (AU connector) cable
YES
YES
NO
Are audio signals inputted to
IC5308 pin5? Failure in the VIDEO SLOT IF board, PCB
connectors, or video slot card. If the audio signal
is output after the video slot card is replaced by a
normally operating one, the removed video slot
card was defective.
YES
Failure in the AUDIO PWB
Failure in the IC3002
Failure in the IC5308
YES
NO
Does the green POWER indicator
repeat a burst of 5 flashes even after
the CN3004 (AU connector) cable is
disconnected?
YES
Is the voltage at Pin 9 of IC3002 4 V or
higher?
YES
NO
NO
Is the voltage at Pin 9 of IC3002 4 V
or higher after the CN3004 (AU
connector) cable is disconnected?
3. Abnormality in audio
Note: Before performing a failure diagnosis, be sure to check that the settings of the unit are properly made by referring to its
specifications and instruction manual.
If speaker outputs with different polarities or a speaker output and ground are short-circuited, the protection circuit is activated,
and audio will not be output. In this case, turn the power off at the Main Power Switch, make connections properly, then turn the
power back on again. The protection circuit will then be released.
Waveform 41
Waveform 42
A