Sharp LC-90LE740X Aquos, Service Manual

Page: 57 / 74

LC-90LE740X
6 – 17
•
Does not sound.
No audio (1)
INPUT-6 No audio. INPUT-5 No audio.
Is INPUT-6 selected on the input select
menu screen? Is INPUT-5 selected on the input select
menu screen?
YES
NO
YES
NO
Refer to “: No external input
video [INPUT-6]”. Refer to “: No external input
video [INPUT-5]”.
Dose the audio signal come from pins (3)
(L) and (4) (R) of input terminal (J514) to
pins (AP34) (L) and (AU36) (R) of IC 3301
(CPU) ? Dose the audio signal come from pins (3)
(L) and (4) (R) of input terminal (J509) to
pins (AP37) (L) and (AR36) (R) of IC 3301
(CPU) ?
YES
NO
YES
NO
Check the line between J514
and IC3301. Check the line between J509
and IC3301.
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 paripheral 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.