Sharp LC-40D68UT Service Manual page 55

No video at UHF/VHF broadcast signal reception
Is the specified TV signal selected on the input select menu screen?
Is there the analog video signal output (VIDEO) at pin (19) of tuner
(TU1101)?
Check the Tuner I2C lines.
1) TU1101: pin (8) (TUN_SDA_C5), pin (9)
(TUN_SCL_C5)
2) SC1101/SC1201: pin (16), pin (15)
3) IC8001: pin (F2), pin (E1)
Check TU1101 and its peripheral circuits.
YES
Is there the analog video signal input at pin (B11) of IC8001
(CPU)?
Check the line between IC8001 and TU1101, and their
peripheral circuits.
1) TU1101: pin (19)
2) SC1101/SC1201: pin (3)
3) IC8001: pin (B11)
YES
Are the LVDS signal outputs at the LVDS 1st channel and 2nd channel of
IC8001?
LV0OUT0P/M (N19/N20), LV0OUT1P/M (N21/N22), LV0OUT2P/M (P19/P20),
LV0OUT3P/M (R19/R20), LV0OUT4P/M (R21/R22), LV0CK0P/M (P21/P22),
LV1OUT0P/M (J21/J22), LV1OUT1P/M (K19/K20), LV1OUT2P/M (K21/K22),
LV1OUT3P/M (L21/L22), LV1OUT4P/M (M21/M22), LV1CK0P/M (L19/L20)
YES
Check the panel module.
No video (5)
NO
NO
6 – 6
No video at digital broadcast signal reception
Are there the video signal outputs (IF_P/N) at the pins (12) and (13) of
tuner (TU1101)?
Check the Tuner I2C lines.
1) TU1101:pin (8) (TUN_SDA_C5), pin (9) (TUN_SCL_C5)
2) SC1101/SC1201: pin (16), pin (15)
3) IC8001: pin (F2), pin (E1)
Check TU1101 and its peripheral circuits.
YES
Are there the video signal inputs at pin (A4)/(B4) (IF_P/N) of IC8001
(CPU)?
Are there IF-AGC signal inputs at pin (F1) of IC8001 (CPU)?
Check the line between IC8001 and TU1101, and their periph-
eral circuits.
1) TU1101: pin (12) (IF_P), pin (13) (IF_N), pin (14) (IF_AGC)
2) SC1101/SC1201: pin (5), pin (6), pin (10)
3) IC8001:pin (A4), pin (B4), pin (F1)
YES
NO Check IC8001 and its peripheral circuits.
(IC8251, etc.)
LC-40D68UT
NO
NO