Recently went through the same with my 2004 Dakota. /replaced the resister etc. failed again within a couple of months. replaced the fan motor, resister, everthing! flawless since. Seems resistance in the wiring causes all the problems. So I had the wiring replaced (where it feeds into the resister). Increased the cost but fixed it!Got it! Behind glove box on end of heater/AC plenum assy. PITA to get it out, the connector has a red locking tab on the side away from me that can't be seen. This tab must be slid sideways to release the connector. The resistor pack is mounted with a pair of small screws I can barely see, TORX. Hard to get my hand in there... But with a few choice words I got it out. Yup, resistor between pins 2 and 3 is open.
My local O'Reilly's has one on the shelf. Hi Ho Hi Ho, to the parts store I go!!
Thank you for your help!!