I have point to the website on another server. After that ajax has blocked on https url. If I run on HTTP then it is working fine.
Mixed Content: The page at 'https://www.exampple.com/' was loaded over HTTPS, but requested an insecure XMLHttpRequest endpoint 'http://www.example.com/checkout/cart/add/uenc/aHR0cHM6Ly93d3cuY2hvY29sYWsuY29tLw,,/product/15/form_key/jPWQ3BJT3TgSpjS9/'. This request has been blocked; the content must be served over HTTPS. send @ jquery-1.10.2.min.js:6 ajax @ jquery-1.10.2.min.js:6 setcheckoutLocation @ (index):23 onclick @ (index):1