If you saw the phrase in front of TV, what kind of impression will you get? To me, I will suppose someone is watching TV. But if so, how do you express the meaning that someone is just in front of TV (talking about the position)?
My first impression is also someone sitting in front of the television; however, seeing as TV is an initialism standing for the etymological roots of television, which is a countable, singular noun, this phrase is missing an article in this context.
Grammatically, as GEdgar pointed out, this phrase could be used to serve as an indication of priority in listing; I'm not aware of any other ways that one could go with that.
It depends on context and the use of the specific verb for what is happening in front of the TV. Put a pillow on the floor in front of the TV, and obviously it's not watching it. If a person is sitting on a chair and a TV is directly in front of them and mentioned, people will (generally) assume it's on and the person is watching it.
"He was sitting in front of the TV eating dinner" assumes that the TV is on. "He was sitting in front of a TV that had landed in the meadow" implies it wasn't. If it's a situation where a person's sitting in the room and the TV isn't on, I would say "across from the TV".