Just to clear up "how you can tell" if your winshield is heated.. Having lines under the wiper is NOT a sure-fire way to know. In 2011 many glass manufaturers switched to laying the heating element under the frit band (the black porceline band surrounding the whole windshield) this was mainly done to smooth the heat pattern under the wipers, but also to make it less of an eyesore. Some may have them clearly visible and orange/rust in color, other may be barely visible because of a thin frit ban, and some not at all visible. It makes no diff when your truck was made. This depends on when the glass manufacturer made the glass
On all 4runners to date, you can tell if the glass itself is heated and connected by pulling your passenger side A-pillar. In the corner near the dash you'll find the wire, and be able to see its connection to the glass. So if there is no wire, there is no heat! This is the positive and neg. and only on the pass side.