I´m trying to serve a pdf file by making a configuration in nginx but I get the following error in the page: 404 Not Found

The configuration is like this:

server {

    listen 3002;
    index index.html;
    server_name _;

    location / {

        root /var/www/html/pdf_carpet;
        try_files $uri /index.html = 404;
    }
}

pdf_carpet is where the pdf file is.

What could I do or change to be able to serve a pdf file in nginx?

P.S. It works with html files.