[sanman28]

Nevermind....I found it.

 

[wiretexspe]

Where is it located? Im gonna attempt to do mine this weekend. 2010 F250

 

[diesel23]

its just under driversside where the obc port /plug in is , theres a bundle of wires taped up , just take your time and go thru them , youll find the purple wire it has a black plastic end on it from the factory, i had to take pics and txt them to the wife saying is this the purple wire !!! gd luck

 

[superdutydixie]

A shop used my purple wire to install my auto start, I had to use the other purple wire that is controlled by the 3rd upfitter switch.