I too have the same symptoms on my D2 w/o rear air. the blower motor works out of the truck, won't work in the truck, relays are good, fuses are good, i couldn't fine the resistor i have heard about, and i took it to a shop. they tell me that i need the "circuit board/fuse block" for the A/C. $650....... now, are we talking about the indash a/c controller unit because i saw one on ebay for $50.