Cruise Control
 

My cruise control stopped working WTF. 05 f-350 6.0l dually

First check for any vacum leaks. If you have no vacum leaks then you must
check each part of the system.

Due to the fact this system is all electronic, it will be hard unless you have a scanner to monitor pids. The circuit uses the brake sw,deactivator sw,servo,clock spring,pcm, and gem module..which make it work, my past exsperience I have replace all at one time or another on different vehicles....to save time and money have it tested at your local dealer/shop....