1. When you say you're plugged into the HD Component section I assume you mean the input section "DTV" (480i,480p,1080i) as all other component inputs are not hi-def. In the manual diagram it's labelled number 7.
2. I've had my set at least 4 years and I've never seen a "DTV HD 16:9" message displayed. The term 16:9 refers to aspect ratio. And I don't know why it would be displayed since 1080i, by default, is 16:9.
Below I describe the messages my set displays:
It always says "1080i" in the upper left corner(if the programming is in 1080i). If I'm watching in 1080i that's all it says. If I'm in 480i it also gives which screen format I've chosen (stretched, zoom, standard etc.) It doens't in 1080i because thet's strictly a native widescreen format that requires no compensation or adjustment. The others are formatted 4:3 so the tv lets you decide how you want the picture fitted to a wide screen display.
3. When you say you watch "24" off of your OTA I assume you mean the "ANT-DTV" input on the far left of your set-back & you're using a conventional antenna at your home to feed it. I don't have that option so I don't know what message the tv would give.
4. To turn the component "DTV" input on or off in the menu:
On my remote I push "Menu". (The following options appear on-screen.)
Hit "Edit Set-Up"
Scroll to "Review" and hit "Next".
The 1080i input is second from the bottom labelled "Input-DTV". (It doesn't say 1080i because 1080i is the only HD signal the tv accepts. )
The next screen lets you name the input or "Finish".
Are you sure the Sat Box is outputting 1080i programming?
Two things to try:
Plug the 1080i outputs from the Sat Box into the non-DTV component inputs on the tv. Find an HD broadcast in the program guide and tune it in on the Sat Box. If it is in 1080i it will be scrambled as the 480i,480p only inputs can't display it.
If you have a friend with an X-Box 360 have them bring it over and hook it up to the "DTV" input. It outputs 1080i. I have one so I'm sure about this. That way you'd know for certain you're getting a genuine 1080i signal.
Since we're getting different messages it makes me wonder if our sets are identical even if the model numbers match.
Let me know how it goes