same problem with 01 highlander. no heat from vents - was able to get heat now and then by sticking a bit of cardboard in between the dial and the dash. we were told by the dealer that we needed the entire heater assembly - that the center dial shorted out and could not be replaced on it's own. using the fix wizzer posted and others tried i can say that we now have heat again and kept $900 in our pockets. thank you all for the pictures and repair information. even if it assembly does go one day it's nice to know i can get a used one and put it in myself for less than $200.
