If you are catching her in the "act" of doing it, then you need to tell her "NO" (so she stops in mid-stream) pick her up and put her on her peepad and don't let her move off of it until has gone. (do you have word for her to pee on command? Like "go potty"?, because you should be doing this the whole time she is on the pad) Now, you may have to wall off or block off the "pee" area so that she can be kept in this area until she does go.
If you have caught her, after she has gone, then you really need to say nothing. Punishing her at this point is uneffective. All they understand is that you are yelling at her for going pee. Dogs cannot discern general concepts. She DOES NOT understand you are yelling at her for NOT going on the pee pad.
The best way to train a yorkie (in my opinion) is to NOT let accidents happen at all. You need to go back to square one and watch her like a hawk, take her to her pee pad regularly, tie her to you if you have to, and never give her a chance to make a mistake, and treat her like crazy every single time! She should have a command name to go potty so that when you take her to her pee pad, and you state the command, eventually she will go as soon as you give her the command.
You should only crate her when you cannot keep an eye on her, like you are cooking or cleaning or going to the bathroom, etc.
This is my recommendation. |