Sharp TU-X1U, Service Manual

Page: 44 / 115

TU-X1U
4 – 17
No audio (1)
INPUT-3 No audio.
Is INPUT-3 selected on the input select menu screen?
NO
Is the audio output selected for "VARIABLE" on the
menu screen?
Set the audio output to "FIXED".
Does the audio signal come from pins(5)(L) and (4)(R) of input termi-
nal(J2201) to pins(40)(L) and (41)(R) of IC1403(CODEC)?
YES
NO
Check the line between J2201 and IC1403.
Does the I2S signal come from pins (4)(COD_LRCK), (5)(COD_BCK) and
(6)(COD_SDOUT) of IC1403 to pins (AK24), (AH24) and (AJ24) of IC8001 (CPU)? NO Check the line between IC1403 and
IC8001, and their peripheral circuits
(X1401, IC1401, etc.).
YES
Does the I2S signal come from pins (AL24)(DSP_MCLK1), (AK25)(DSP_BCKIN1),
(AJ25)(DSP_LRCK1), (AL25)(DSP_SDIN1) of IC8001 (CPU) to pins (5), (11), (10), (9) of
IC4504 (HDMI_Tx) NO Check the line between IC8001 and
IC4504, and their peripheral circuits.
YES
Does the HOT PLUG detection function?
Is the DDC5V signal output at the pin (18) of SC4501 (HDMI_OUTPUT)?
NO Check the line between SC4501 and
IC4503, and their peripheral circuits.
YES
Does the HPD signal come from pin (19) of SC4501 (HDMI_OUTPUT) to pin (51) of
IC4504 (HDMI_Tx)? NO Check the line between SC4501 and
IC4504, and their peripheral circuits.
YES
Check the HDMI cable and Monitor Unit.
Are there the TMDS signal outputs at pins (12/10)(CLK-/+), (9/7)(D0-/+), (6/4)(D1-/+), (3/
1)(D2-/+), all of SC4501 (HDMI_OUTPUT)? NO Check the line between SC4501 and
IC4504, and their peripheral circuits.
YES
Check the HDMI cable and Monitor Unit.