Service manual

31
LC-20VM2
LC-121M2E
LC-150M2E
Check in/output voltages of IC406.
YES
No colour appears
No colour (AV1, AV2 and Component)
Is output voltages
at pins 3 and 6 of
IC406, IC451
normal?
Check peripherals.
Are these voltages
as follows of IC801
normal?
pins 51 and 52
(input)
pins 41, 42 and
43 (output)
Check IC801 and
its peripheral
parts.
No colour (AV1, AV2)
Is output voltages
at pin 6 of IC407
normal?
Is input voltages
at pin 13 of
IC801 normal?
Is output voltages
at pins 5 and 6 of
IC801 normal?
Check in/output
voltages of IC406.
Check IC407 and
its peripheral
parts.
Check peripherals.
No colour (Component)
YES
YES
YES
NO
NO
NO
NO
NO
Check IC801 and
its peripheral
parts.
No sound
Is 13V applied to the pin 9 of IC305?
Muted. Check
the FSMUT line.
Is the pin 9 of
IC2001 in the
"L" state?
Check IC308,
IC316 and their
peripherals.
Check speaker
unit and its
peripheral parts.
Is the pin 10
of IC2001 in the
"L" state?
Is output at pins
1 and 7 of
IC316 normal?
Is output at pins
10 and 17 of
IC305 normal?
Is output at pin
14 of IC305
normal?
Is the pin 5
of IC2001 in the
"L" state?
Check Q305,
J4001 and their
peripherals.
YES
YES
YES
NO
Check IC305 their peripherals.
YES
YESYES
YES
NO
NO
NO
YES
Check IC308,
IC304 and their
peripherals.
Is output at pin
7 of IC304
normal?
NO
Check Q308,
F703 and their
peripherals.
NO
YES
YES
YES
Check IC317 and
their peripherals.
Is output at pins
1 and 7 of
IC317 normal?
NO
Check IC313,
IC314 and their
peripherals.
Is output at pins
1 and 7 of
IC314 normal?
NO
YES
NO
NO
Check the
LSMUT line.
NO
Muted. Check
the RSMUT line.
Does not output from the front Does not output from the rear Does not output from the headphones Does not output from the line output
Is the pin 24
of IC2001 in the
"L" state?
YES