I have been looking for info on enabling daytime running lights on my 04 Coachmen Cross Country in order to satisfy mandatory laws for vehicles imported into Canada. Thought I would pass along my experience. I suspect this is the same for most makes and models.
Most newer vehicles have the option for DRL. Check the fuse control box to see if there is a fuse/relay placement labeled DRL. You can contact your local Freightliner dealer and ask for the appropriate module.
In my case however, my local Freightliner dealer informed me that my particular model (I provided the VIN #) did not have that option. I then contacted the tech service folks at Freightliner Custom Chassis Corp

, who advised me that it did indeed have the option and told me where to look (lower left of steering column) for the placement. They then gave me the part #SPW 1325F. I went down to my local Freightliner dealer and picked up the module. Cost was $46.68 CAN (taxes in). I have yet to install it, but have been told by FCCC techs it is "plug and play".
Hope this helps others.