How to connect my devices

[tiajerry37]

How do I connect my LG TV Model: LG 55LF6100 to my sony home theatre system Model:HBD-1DZ170

 

[Barty1884]

Looks like that's just a model number for the receiver, not for the system itself.
Is this the system you have? https://esupport.sony.com/US/p/model-home.pl?mdl=DAVDZ170&LOC=3#/howtoTab

And the TV:
https://www.lg.com/us/tvs/lg-55LF6100-smart-led-tv

As per the marketing spec here:
https://esupport.sony.com/US/p/model-home.pl?mdl=DAVDZ170&template_id=1&region_id=1&tab=manuals#/manualsTab

You should be able to run HDMI from the receiver to the TV, which should achieve what you want.
Or you could use Toslink (Digital optical) from the TV to receiver.

 

[americanaudiophile]

That HTS may not support HDMI-ARC so the HDMI output would be for disc playback only. Use the optical audio output of the TV. Check the TV manual on how to turn on and configure the output. You may have to turn the TV speakers off.