Astroboy,

I encountered the same thing when I took the rear vent panel out. There were no connectors for the rear heated seat switches. Were you able to find them? I haven't looked under the carpet, but when I lift the rear bench seat, it has the proper Heated Seat wiring harnesses. That leads me to believe that the wiring should lead to the switch harnesses. Any luck finding them?

FYI - I have a 2004 4.4 with Premium and Cold Weather/Rear Climate packages, without heated rear seats (though wiring harness is there). I thought if those were present, the wiring harnesses/connectors should be there for switches to go in.