Does one make another Bracha on tefillin after removing them to use the bathroom?
There is a discussion as to whether one should make a new bracha in this case. Some say that since it is forbidden to enter a bathroom with tefillin, it is considered as is he has diverted his mind away (היסח הדעת) from the fulfillment of the mitzva, and therefore has to make a new bracha when he puts them on afterwards.
Many poskim say that the halacha is that one must make a new bracha (Mishna Berura 25: 47), however others say that one should not make a new bracha (Kaf Hachaim 25: 78). Many people (even ashkenazim) follow the latter view that we do not make a new bracha, especially if having only urinated, and all the more so when having only visited a urinal and not entered a real bathroom (Shut Shevet Halevi vol 9: 3, Shut Tshuvos Vehanhagos vol 1: 43).