Check the PC I/F unit.
<When COMPONENT/DVI signal is received> No image (3)
No COMPONENT image on INPUT1
Has "INPUT1" been selected 
on the Input Select screen?
Are RGB signals applied to 
pins (63), (59) and (61) of 
IC1401 (AV switch)?
Select INPUT1 
COMPONENT
 on the 
Input Select screen.
Check lines and devices 
between pins (8), (26), (17) 
of J1103 (INPUT1) and 
pins (63), (59), (61) of 
IC1301.
No 
COMPONENT
 image on INPUT3
Has "INPUT3" been selected 
on the Input Select screen?
NO
NO
YES
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
YES
YES
NO
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
Select INPUT3 
COMPONENT
 on the Input 
Select screen.
Are RGB signals applied to 
pins (9), (5) and (7) of 
IC1401 (AV switch)?
Check lines and devices 
between pins (8), (26), (17) 
of J1104 (INPUT3) and 
pins (9), (5), (7) of IC1301.
No DVI image on INPUT3
Has "INPUT3" been 
selected on the Input Select 
screen?
Select INPUT3 DVI on the 
Input Select screen.
Are DVI signals applied to 
pins (2), (3), (5), (6), (48), 
(49), (51), (52) of IC1650 
(DVI D/A)?
Check lines and devices 
between SC1650 (INPUT3) 
and IC1650.
NO
YES
YES
Are RGB signals applied to 
pins (23), (26), (31) of 
IC1650?
Check peripherals of IC1650 
(DVI D/A).
NO
YES
Are RGB signals applied to 
pins (15), (17) and (19) of 
IC1401 (AV switch)?
Check lines and devices 
between pins (23), (26), (31) 
of IC1650 and pins (15), 
(17), (19) of IC1301.
Are the MAIN video signal sent from (46)/(50)/(48), PASS signal sent from (34)/(38)/(36) and SUB video signal sent from pins (4
0)/(44)/(42) of IC1401 respectively?
Are Y/Cb/Cr signals applied to pins 
(19), (18) and (17) of IC801 (MAIN 
VIDEO CHROMA) respectively?
<MAIN 525i system>
<PASS 525P/1125i/750P system>
Check lines and devices between 
pins (46), (50), (48) of IC1401 
and pins (19), (18), (17) of IC801.
Are the MAIN-Y/Cb/Cr signals 
sent from pins (21), (22) and 
(23) of IC801 respectively?
Check IC801 (MAIN 
VIDEO CHROMA) and its 
peripheral circuits.
Are the MAIN-Y/Cb/Cr signals 
applied to pins (69), (68) and 
(67) of IC803 respectively?
Check lines and devices 
between IC801 and IC803.
(IC814, Q814-5, etc.)
Are Y/Cb/Cr signals applied to 
pins (5), (4) and (3) of IC803 
(RGB DECODER) respectively?
Check lines and devices between 
pins (34), (38), (36) of IC1401 
and pins (5), (4), (3) of IC803.
Are the MAIN-R/G/B signals 
sent from pins (35), (37) and 
(39) of IC803 respectively?
Check IC803 (RGB DECODER) 
and its peripheral circuits.
Are the MAIN-R/G/B signals 
applied to pins (3), (7) and 
(10) of FL810 (6.7/30 MHz 
L.P.F.) respectively?
Check lines and devices 
between IC803 and FL810.
(Q801-3 etc.)
Are the MAIN-R/G/B signals 
sent from pins (19), (15) and 
(12) of FL810 respectively?
The cutoff frequency of FL810 
(L.P.F.) is switched as follows 
depending on the input 
signals:
Status of pin (17) for setting the 
cutoff frequency of FL810 (6.7/30 
MHz L.P.F.)
<525i system>: High
<525P/1125i/750P system>: Low
Check FL810 (6.7/30 MHz L.P.F.) 
and its peripheral circuits.
<SUB system>
Are Y/Cb/Cr signals applied 
to pins (19), (18) and (17) 
of IC802 (SUB VIDEO 
CHROMA) respectively?
Check IC1401 (AV switch) 
and its peripheral circuits.
Check lines and devices 
between pins (40), (44), (42) 
of IC 1401 and pins (19), (18), 
(17) of IC802.
Are the SUB-Y/Cb/Cr signals 
sent from pins (21), (22) and 
(23) of IC802 respectively?
Check IC802 (SUB VIDEO 
CHROMA) and its peripheral 
circuits.
Are the SUB-Y/Cb/Cr 
signals applied to Q901-2, 
Q903-4 and Q905-6 (6.7 
MHz L.P.F.) respectively?
Check lines and devices between 
IC802 and Q901-2/Q903-4/Q905-
6 (6.7 MHz L.P.F.).
Are the SUB-R/G/B signals 
sent from Q901-2, Q903-4 
and Q905-6 (6.7 MHz 
L.P.F.) respectively?
Check peripherals of Q901-
2/Q903-4/Q905-6 (6.7 MHz 
L.P.F.).