Sharp LC-90LE740X - HDMI AUDIO TROUBLESHOOTING

LC-90LE740X
6 – 20
No audio (4)
INPUT-1 No audio (HDMI connected)
INPUT-2 No audio (HDMI connected)
INPUT-3 No audio (HDMI connected)
INPUT-4 No audio (HDMI connected or MHL connected)
[INPUT-1 input]
Is INPUT-1 selected on the input select menu screen?
[INPUT-2 input]
Is INPUT-2 selected on the input select menu screen?
[INPUT-3 input]
Is INPUT-3 selected on the input select menu screen?
[INPUT-4 input]
Is INPUT-4 selected on the input select menu screen?
YES
NO
Refer to “: No external input video [INPUT-1/2/3/4]”.
[INPUT-1 input]
If no video appears, refer to “No external input video (HDMI) [INPUT-1]”.
[INPUT-2 input]
If no video appears, refer to “No external input video (HDMI) [INPUT-2]”.
[INPUT-3 input]
If no video appears, refer to “No external input video (HDMI) [INPUT-3]”.
[INPUT-4 input]
If no video appears, refer to “No external input video (HDMI) [INPUT-4]”.
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)?
YES
NO
Check the line between IC3301 and IC1703 and their peripheral circuits.
• 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)?
YES
NO
Check IC1703 and its paripheral circuits.(X1701, etc.)
• 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?
YES
NO
• About the L/R Speakers.
Check IC1902 and its peripheral circuits.
• About the Subwoofer Speaker.
Check IC1901 and its peripheral circuits.
• 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.