Which cable box or PVR? It could be something as simple as the TV channel being accidentally changed away from Ch 3.
Verified box has a green light showing on front of cable box and the tv is powered on
Select cable and power. Seclect the guide button. Does it show? If you do see the guide give rogers a call.
If not it is most likely and imput Issue and you would need to find the Imput or source button and choose HDMI or Video option on your tv until you see your channels.
I HAVE HAD GOOD SERVICE FROM ROGER EMPLOYEES! ABOUT 3 WEEKS AGO I HAD A TECH COME TO MY HOUSE FOR BLACK BOX MOTOROLA REPAIRS! HE INSTALLED 2 H.D. BOXES.AFTER A FEW DAYS WITH THE REMOTE, "NO SIGNAL" ON SCREEN!! ANOTHER EMPLOYEE ARRIVED, PUSHING REMOTE BUTTONS AND WORKING AGAIN!! IN A FEW DAYS."NO SIGNAL" AGAIN. ANOTHER EMPLOYEE ARRIVED, MADE SOME CHANGES AND EVERYTHING WORKING!!AFTER A FEW DAYS "NO SIG!! SOLUTION--MAY I HAVE AN EMPLOYEE COME AGAIN AND PUT 2 SMALL BOX MOTOROLLAS BACK ON. I AM AN 80 YEAR OLD DISABILITY CUSTOMER,HOME MOST OF THE DAY!! THANK YOU IN ADVANCE, WAYNE
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dunn7vic's post describes a problem I have every once in awhile. For me the problem is usually that the box and the TV have gotten out of sync, When the TV shows "No Signal" I just have to push the power button on the PVR box. They tend to get out of sync when I turn the TV off and set down the remote too quickly or some piece of furniture slightly blocks the remote signal.
As Lurker mentioned sometimes it is the wrong buttons getting accidently pushed.
e.g. Every once I awhile my husband accidently hits the DVD or AUD button. In that case just pushing the TV button followed by pushing the Cable button sets thing back to normal.
Lurkers suggestion to get the tech to write down the instruction sounds like a good idea. Good luck in getting it sorted out