1999 Chrysler Cirrus Chrysler code P1776

The code keeps popping up and we have no idea what to do for it or where the parts that need to be replaced are just any information and pictures on where and what i'm supposed to do for this code would be fantastic. My father in law is a mechanic and even he is stumped by this. Oh and I have no idea how many miles are on the car but there are alot