When one takes down a mezuzah to be checked, does it get put back on with a bracha or not?
Answer:
If it was only down for a few hours [not overnight] AND it was found to be kosher, no new bracha is made.
If it was down overnight OR found to be non kosher and fixed a new bracha would be made.
Sources:
Aruch Hashulchan Y:D 289:4