Oldsmobile/Buick Repair: Buick horn wont work, buick lesabre, close fit

Question
My father-in-law took his 95 Buick LeSabre to a
service station to get the annual state inspection.  They discovered the horn did not work.  They checked fuses and poked around on the wires but no luck./ He had a battery recently installed at Walmart.  Could they have
affected the horn somehow?  Is there something simple I might try or should he just take it to the dealer?

Answer
Hi herschel,
If I am not mistaken, the horns are very near the battery, and with the close fit I have seen in some of the vehicles lately, they could very easily have knocked something loose, such as the connector on the horn relay, or left a ground wire loose.
I think you may need to remove a support strut to get to the battery, at least you do on a 95 Cutlass.
They may have even needed to disconnect a wire, but could also have pinched it with the battery or bracket.
Normally, though, pinching a wire will ground it, which will blow the fuse.
That is sure the area I would check first though.
Good luck,
Van