new furniture

Question
Hello,
I have a 2yr old boxer/bulldog that jumps  on my new couches when I'm not home. He was never allowed on the couches before nor will he do it when I'm home. I'm 100% sure he is on the couches when I'm not there because when I get home his hair is where he was laying down and the spot is still warm. So he's jumping off when I'm at the door. How can I train him to not jump on the couches when I'm not there?? Again he never tries when I'm home.
                             Thanks for the time
Ps. He does have a crate with a fluffy pillow and an old tshirt of mine in the living room. So he does have his space with my scent. I'm lost please help save my couches

Answer
Hi,
there is two things to try, since he knows what not to do. One is to get several mousetraps and set them on the couch.  Cover them with a one or two sheets of newspaper.  When he jumps up the traps should go off and the sound may scare him enough so he won't do it again.
Two  leave the house with a window partially open.  Drive away a bit and then quietly walk back and peek through the window.  Use a shake can and loud "NO" if he is on the couch.
Three at petedge.com there is a pad that sends a vibration and a mild shock if he gets on the couch.

One of these should work
nancy
PS a shake can is a coke can with 7 pennies in it and the top taped.