LC-80LE857E (serv.man4). March 2013 - Sharp TV Service Manual (repair manual). Page 48

LC-80LE857E/K/RU,LE858E

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Does not the sound of the audio signal output to HDMI1 go out?

Does audio signal output from pin[14] of SC1501 (HDMI1 terminal) ?

YES

Check SC1501 and peripheral circuits.

NO

Does audio signal output from pin[39/HECP] of IC2601(HDMI-SW) ?

YES

Check  the line between IC2601 and SC1501.

NO

Does audio signal input to pin[36/HDMI_ARC_SPDIF] of IC2601 ?

YES

Check IC2601 and peripheral circuits.

NO

Does audio signal(HDMI_OPT_OUT) output from pin[Y32/
CPU_ASPDIF1] of IC3301(Digital AV decode & Main CPU)?

YES

Check the line between IC3301 and IC2601.

NO

Check IC3301 and its peripheral circuits.

The picture doesn't appear in all modes.

Is the signal output from IC3301(DIGITAL_AV_DECODER_&_MAIN_CPU) respectively?
[VBO_TXA+-(AT4/AU7),  VBO_TXB+-(AP3/AR3),  VBO_TXC+-(AT2/AU2),  VBO_TXD+-(AR1/AR2)]

YES

NO

Check IC3301 and its peripheral control circuits.
(IC2004, IC3501, IC3502,  IC3503, IC3504, X3301, etc.)

Do above-mentioned signals output from connector 
(SC3801) ?

NO

Check the line between IC3301 and SC3801.

YES

Similarly, is LCD controller's control signal normal ?

NO

Please check each control signal of DET_POW(DET_PNL12V), 
PE(PNL_EN).

YES

LCD Controller Unit: 
Do signals input to connector(LW) of LCD Controller Unit ?

NO

Wire harness (LV) is checked.

YES

Check the panel module.