I have a LG Studioworks 77i 172 monitor that after a period of time [2 to 6 hours]. switches off.Particularly in high temperature room.It will go again after a while.
I belive there is a component that controll the temperature to renew.I can not possibly find out which.
Is it a termistor?> I have a schematic available.
I f anyone can help ,please e-mail or post the reply.

There is no temperature switch in any monitor. What you have is a thermal runaway issue caused by an excessive ambient temperature on a weak component. This one would be a bitch to fix,

check the screws on the heatsinks. Maybe some component is not properly mounted on its heatsink.
Sometimes it is horizontal output transistor.