Jquery CodeIgniter 2.X

Autocomplete is an ajax request so your contoller needs to echo results. Also you are using it wrongly as you need to define the serviceUrl: which returns the option data or provide the option data manually.

Have a look here:
https://www.devbridge.com/sourcery/compo...ocomplete/

Or the API docs
http://jqueryui.com/autocomplete/

Hope that helps,

Paul.