I have a 4 mo old yorkie that seems to urinate in his crate. I used to put a potty pad in his crate and then I stopped. He stopped having a bowel movements in the cage and would not pee, well so I thought. I noticed when I would get home, he would smell like urine, but his tray was dry. Well Sunday I noticed that his tray was wet, so it appears that he is urinating in his crate during the day, and laying in it. I am having to bathe him daily when he is left alone in the crate. He does not urinate in the house, he goes outside. He does not like to be left in his crate at night to sleep, or when we leave for work.
How big is his crate? It should be only large enough to sit up, tunr around, and lay down in. If he has an accident, he should not be able to get away from if, he should be have to sit/lay in it. That is what discourages him from going in the crate. Don't put a pee pad in the crate, that will encourage him to go there, if you are pee-pad training. How long are you leaving him in the crate at a time? Yorkies have small bladders and are known to be hard to housebreak. A four month old puppy is still pretty young, I would still be taking it to potty at least every 2 hours, though he may be able to hold it longer. Also, even if you have him crated I would be checking him visually even more often then that. He may start the habit of eating/drinking the evidence, so dry floors are still suspect.
Ok A 4 month old puppy can't hold it 8 hours yet. You are lucky if he makes it through the night 8 hours now, but he can't hold it 8 hours at night, and 8 hours in the day. He's still developing. It may be another 4 months or so until he's able to do that so, please don't crate him that long! I know its necessary for you to leave him that long, but if you can't find someone to let him out once or twice during that time, then instead of crating, get an xpen, or leave him closed up in a puppy proofed room. Keep the crate in their with him, door open. Leave down some pee pads to use while your away, he needs to be able to go somewhere and not be in trouble for it. Also leave some toys, water, etc. Then he will be able to keep himself entertained, have a place to pee, be able to get into his crate to relax, drink some water during the day and not be dehydrated, not be in trouble for destrying some part of the house, not have to be bathed twice a week which is bad for his skin, etc.