Just recently, my camper, on a Dodge Ram3500 1997 has only one blower position, HIGH. I hate to go to the dealer if it's an easy fix. Can anyone give me help and advice? I believe it's not a fuse, but a relay. I have checked the manual at the relay distribution panel, and I am not sure which governs the blower motor, or if there is a relay right on the blower motor.

 

I don't know exactly what your problem is, but I have a '97 1500 that had leaves and crap in the fan (under the dash on passenger side) and it only worked in High untill I cleaned it out. As for the only defrost setting, that is a vacumm problem probably (the controls are vacumm and defrost is the default position). I know this because I used to have a bad vacumm leak and everytime I put my foot into it my heat/ac would go to defrost.

 

It's your blower motor resistor block.
EASY fix, and cheap part too.