Q. Somebody stumbled and hit on my mezuza, and it remained barely hanging only from one single mostly detached nail. It looks as if it can just fall off completely anytime. If I nail it back in place, do I have to say a brocho?
A. Pischei Teshuva (Y.D. 289: 1) quotes different opinions if one has to recite a brocho when he takes off a mezuza to check it, and replaces it back. He compares it to taking off a taalis when having in mind to wear it again. However, he rules that if the mezuza fell by itself, one has to recite a brocho when it is replaced. Others disagree and maintain that it may depend on the time elapsed and other factors. See Pischei Mezuzos ( 289: 1) for a summary of the different opinions. He also mentions that if the mezuza remained attached only by the bottom nail and it even reversed itself, he should not make a brocho, as it is analogous to a taalis that fell only partially.
Horav Shlomo Miller’s Shlit’a opinion is similar and no brocho should be recited.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit’a