Sharp LC-70UD1U Service Manual page 59

[PC analog audio input] INPUT-8 No audio.
Is INPUT-8 selected on the input select menu screen?
NO
Refer to ": No external input video [INPUT-8]".
YES
Is the audio output selected for "VARIABLE" on the menu screen?
NO
Set the audio output to "FIXED".
YES
Is the "Terminal Setting" - "Audio select" selected for "Video +
Audio" on the menu screen?
NO
Set the HDMI audio output to "Video+Audio".
YES
Does the digital audio signal come from pins(AR11/AP11/AN9)(CPU_AOBCK/AOLRCK/AOSDATA0) of IC3301(CPU) to pins(6/7/5)(SP_BCLK/
SP_LRCLK/SP_DATA) of IC1703(Audio DSP)?
NO
Check the line between IC3301 and IC1703 and their peripheral circuits.
YES
• About the L/R Speakers.
Does the digital audio signal come from pins (30/21/26/27) of IC1703 (Audio DSP) to pin (5/7/8/6) of IC1902 (AMP for L/R)?
• About the Subwoofer speaker.
Does the digital audio signal come from pins (30/21/26/28) of IC1703 (Audio DSP) to pin (5/7/8/6) of IC1901 (AMP for SW)?
NO
Check IC1703 and its paripheral circuits.(X1701, etc.)
YES
• About the L/R Speakers.
Is the audio output from IC1902 as specified?
• About the Subwoofer Speaker.
Is the audio output from IC1901 as specified?
NO
• About the L/R Speakers.
Check IC1902 and its peripheral circuits.
• About the Subwoofer Speaker.
Check IC1901 and its peripheral circuits.
YES
• About the L/R Speakers.
Check the connector (P1903) L/R speakers and their peripheral circuits.
• About the Subwoofer Speaker.
Check the connector (P1904), subwoofer speaker and their peripheral circuits.
No audio (2)
[HDMI analog audio input] INPUT-2 No audio.
Is INPUT-2 selected on the input select menu screen?
YES
Is the audio output selected for "VARIABLE" on the menu screen?
YES
Is the "Terminal Setting" - "Audio select" selected for "Video +
Audio" on the menu screen?
YES
6 – 15
NO
Refer to ": No external input video [INPUT-2]".
NO
Set the audio output to "FIXED".
NO
Set the HDMI audio output to "HDMI+Analog".
LC-70UD1U