Option One:
NISSAN VEHICLE WARRANTY
Nissan vehicles are covered by a new vehicle limited warranty, and almost all come with a 3-Year / 36,000 mile limited warranty (whichever occurs first) and a 5-year / 60,000 mile limited warranty for powertrain components (whichever occurs first). See your Dealer or warranty information booklet for relevant information.
You've stated that you've owned it for just under three years. If the odometer is under 36,000 miles, you can have the dealership fix it for free. If you meet the criteria, I'd take the car in before the warranty expires.
Option Two:
Here at NICO, we have Factory Service Manuals available free to members. While we don't at present have the FSM for the 2017, the info for the horn will be the same as what can be found in the 2016 FSM. Here's the direct link to the horn section:
https://www.nicoclub.com/service-manual ... H%22},820]