Let's get some facts established:
The assumption is that you are using a dual tuner (e.g. 322, 625, 622, 722, etc.)
Typically the second tv is fed out on channel 60 "Air" not cable, to verify that, on the TV1 remote hit Menu, then 6 for system setup, then 1 for installation, then modulator (note that on some receivers that is a little bit different, on some models it appears on the system information screen accessed by hitting menu twice). Anyway, it is here that you will see if it is set to cable or to air.
Now, go into your bedroom and ensure that the cable is connected directly to the back of the television. Then, using the television menu either via the television remote or the buttons on the front have it do a channel scan. If your modulator is set to cable then tell your TV to scan for cable channels, if it set for air then tell your TV to scan for air. If you cannot choose one or the other just do a scan and see what comes back. If you get nothing then back on TV1 you can try switching to the other one (ie. air to cable or cable to air) and then running the scan again. If that is not working try to manually type in the channel number listed on the TV1. If nothing has worked at this point then you might need someone to come out and fix it.
Now, if you are NOT running a dual tuner (ie. you have a receiver in your bedroom as well) then everything is different. In this case you would need to determine how it is connected to the television. Look on the back and see which wires go to the TV. If it is a single cable with a flat rectangle connector then it is an HDMI and you need to select the corresponding HDMI input on your TV. If it is 3 RCA plugs (red, white, yellow) then you need to select the corresponding input (sometimes called AV) on your television. If it is a single coaxial cable then you need to select channel 3 or 4 (usually 3).
Again, make sure that all the cables are securely attached (we all make those mistakes sometimes).
Hope that this information has been helpful.
Note: If you are getting an ACTUAL DISH NETWORK message in the bedroom stating "Error 015" or "Complete signal loss" then again that is another problem. In the instance of the dual tuner and TV1 is fine but TV2 has no signal then that is definitely some sort of equipment failure. If it is a single tuner then it is either cabling or equipment. However if all you see is a black screen and it says no signal (or you get static) then it is a TV connection problem not necessarily a DISH signal problem.
If it is tv 2 and no vcr is connected inline, then the tv needs to be tuned to ch 3. if it is tv 1, ie the tv is in the same room with the receiver, tie tv needs to be on an input setting such as av, comp, video or hdmi. Also check the cables and make sure they are tight. If none of this works try replacing the cabling.