Hi, BonCoeur! I have two 5 month old yorkies myself, Parker and Duke. I am doing the exact opposite and training them to go potty indoors in their potty cage. One has it down, the other...not so much
Anyway, I have a couple suggestions that Ihave read about for you. First of all, I noticed that when I tokk my boys on their walks, they didn't go potty at first. However, on day I decided to go for a run with them. I'll tell you, once they started running, it wasn't 10 yards before they had to go to the bathroom. You may want to try running with them a few times just to get them used to using the outdoors as their new bathroom. Another suggestion. Natures Miracle makes puppy pads that have a grass scent to them. They say day by day move the pads closer to the door that you will let your puppy out at. Once he is going by the door, move the pads outside and take him to it each time. Eventually he should start going outside without the pads. Hope that helps