Re: wiring diagram
The how too tech guides for the muth heated / turn signal mirrors might offer some value.
As well this site has a lot of wiring diagrams for different vehicles so could be useful for the stock power mirror wiring or other vehicles with heated.
Under automotive ref
2010 B4000 4x4 SE+
mods:Tinted windows,Line-X,BAK Rail Caps,rust proofing, stebel natilus air horn,ScanGauge II,hitch reciever cover, Belkin Iphone mount charger, rubbermaid floor mats, hose clamp tailgate, mud flap delete, Cargo light 3rd brake light, explorer lighted visors, mustang dome light, fog light mod, Mountaineer ohc, bosch evolution wipers, GenK51a mirror,Kenwood p680c speakers, Underhood LED's, Ranger winter rims 245/75-16 Blizzak DMV-1's, 180lbs winter bed weight