If yopu are looking down on the faces you are wanting to constrain together then use the Select Other tool. If you are looking at the side of the faces you are wanting to constrain then the answer is "no", you can't select faces from a side view. Only edges and points. Not sure why anyone would want to constrain like this. Even in MDT I never worked this way.
If you are wanting to place a constraint while looking at the side view then go to the Window pull down and select New Window. Then the Window pull down and select Arrange All. Now you can place the constraint in the ISO view while watching the result in the side view.
MechMan