My 2007 is250 AWD did not come with the heated windshield de-icer option (third button is blank next to headlight cleaner). Would the dealer be able to install that option or a DIY assuming I first buy the oem heated windshield to start with. Any help or info would be appreciated, thx.

 

There is no such option. The windshield is de-iced by hot air from the defroster, which is part of the climate control system.

 

I think the missing button was for the laser cruise control. There's no heated windshield or heated deicer on any MY, AFAIK. Definitely not '07.

 

You can install an aftermarket solution to fit your needs; definitely not something that came stock on these things.