The dash control unit for the heater and air conditioner was loose.
The fan control was not held at all and could be pushed through the
panel. The buttons were not solid as well, particularly the right most
buttons. It bothered me, I like everything to work properly.
It was clear that the switch had broken away from it's mounting.
It looked like this;
You will have to pull the dash instrument panel away from the dash
as far as possible to get at the control. Putting the shift lever in
1 position (lowest position) worked best for me.
The plastic control is held in by two screws on either side. If you
remove the nuts then the control can be removed from the dash
panel. The bolts themselves are permanently attached to the dash
panel so you don't have to worry about loosing them.
I bought a new plastic control housing from eBay. It was called:
"Control Housing A/C and heater Dodge Van 1997 Mopar 5011344AA"
It is a perfect match. Here it is assembled with the parts from the
old broken one. The button assembly unscrews from the housing
and I left it fully attached in the dash.
New on on the left, broken one on the right.
The temperature control lever was stiff. This was due to binding in the
cable that attaches the control lever to the heater water valve. I used
the old motorcycle trick to lubricate the cable.
Take a plastic sandwich bag and poke the cable through the bottom
of the bag. Use a rubber band to hold the bag tightly against the
cable's plastic sheathing. Wind the rubber band around the bag
many times to form a tight seal. Fill the plastic bag with oil enough
that the oil level is above the cable sheathing. Hold it up as high
as you can and leave it for a few hours. I taped the bag to the
dash with duck tape and left it overnight. I put some rags under
the cable to catch any oil that might leak. I could see that the oil
and come all the way through and was on the water valve.
I reassembled everything and it was good as new!
If people don't want to hear about all this minutiae tell me and I