Looking for advice please
I have a Sharp 50 inch led tv model LC-50LE752E when I plug into mains I get a steady red light on the front but no picture or sound I have checked the caps on the PSU and they appear to be ok
Looking for advice as to what to do next please
A steady red light usually means it's stuck in standby.
You need the circuit diagram and/or service manual, a multimeter and the ability/knowledge on how to go about fault-finding.
The latter is beyond the scope of internet forums.