XG-MB70X (serv.man13). Troubleshooting - Sharp Projector Service Manual (repair manual). Page 7

Send RGB signals to INPUT1 
or INPUT2. Use keys on the 
main unit or remote control to 
select INPUT1 or INPUT2.

Are sync signals input to pins 
(30) and (31) of IC3005?

Go to "Checking the sync 
signal".

Are picture signals input to pins 
(43), (48) and (54) of IC3005?

 Are picture signals input to 
pins (2), (5), (11), (3), (6) and 
(10) of IC3003?

When toggling between INPUT1 
and INPUT2 by using keys on 
the main unit and remote 
control, does the voltage of pin 
(1) of IC3003 change?

Replace IC3003.

Check Q3123, IC2003 and 
peripheral circuits.

Are picture signals input to pins 
(1), (5) and (8) of IC4003, and 
pins (1), (5) and (8) of IC4004?

When toggling between INPUT1 
and INPUT2 by using keys on 
the main unit and remote control, 
does the voltage of pins (2), (4) 
and (7) of IC4003, and pins (2), 
(4) and (7) of IC4004 change?

Check IC4009, IC2003 and 
peripheral circuits.

Check SC4003, SC4001 and 
peripheral circuits.

Replace IC4003 or IC4004.

Are picture signals input to pins (43), 
(48) and (54), and sync signals input 
to pins (30) and (31) of IC3005?

Check IC3106, 3107, 3108 
and peripheral circuits.

Are sync signals output from pins 
(64), (65) and (66), and sine wave 
output from pin (67) of IC3005?

Check IC3005 and peripheral 
circuits.

Are signals input to pins (56), 
(58), (62) and (64) of SC2501?

Check IC8001 and peripheral 
circuits.

Go to "Checking the peripheral 
circuits of the formatter".