Sharp TU-X1U Service Manual page 46

TU-X1U
No audio at UHF/VHF broadcast signal reception.
Is TV selected on the input select menu screen?
Is the audio output selected for "VARIABLE" on the
menu screen?
Set the audio output to "FIXED".
YES
Is there the SIF signal output at pin (15) of tuner (TU1101)?
Check the tuner (TU1101) and its peripheral circuits.
YES
Does the SIF signal come from pin(15) of tuner (TU1101) to pin
(AN23) of IC8001 (CPU)?
Check the line between TU1101 and IC8001, and
their peripheral circuits. (Q1101, Q1102, etc.)
TU1101 pin (15)
P1101 pin (10)
SC2202 pin (10)
IC8001 pin (AN23)
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)
YES
Does the HOT PLUG detection function?
Is the DDC5V signal output at the pin (18) of SC4501 (HDMI_OUTPUT)?
YES
Does the HPD signal come from pin (19) of SC4501 (HDMI_OUTPUT) to pin
(51) of IC4504 (HDMI_Tx)?
YES
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)?
YES
Check the HDMI cable and Monitor Unit.
No audio (3)
NO
NO
NO
No audio at digital broadcast signal reception.
Is TV selected on the input select menu screen?
Is the audio output selected for "VARIABLE" on the menu screen?
Set the audio output to "FIXED".
YES
Are there the video signal outputs (IF_OUT_PT/NT) at the pins (19) and (20)
of tuner (TU1101)?
Check TU1101 and its peripheral circuits (SDA3_5/SCL3_5, etc.).
YES
Are there the video signal inputs at pin (AM33) and (AM34) of IC8001 (CPU)?
Check the line between TU1101 and IC8001, and their peripheral
circuits (L2204, C2229, etc.).
TU1101 pin (19)(P)
P1101 pin (6)
SC2202 pin (6)
IC8001 pin (AM33)
YES
NO Check the line between IC8001 and IC4504, and
their peripheral circuits.
NO Check the line between SC4501 and IC4503, and
their peripheral circuits.
NO Check the line between SC4501 and IC4504, and
their peripheral circuits.
Check the HDMI cable and Monitor Unit.
NO Check the line between SC4501 and IC4504, and
their peripheral circuits.
4 – 19
NO
NO
NO
pin (20)(N)
pin (5)
pin (5)
pin (AM34)