My 1999 intrepid climate control only blows through the dash

Could be the controller or a faulty blend door.
The blend doors direct air thru the heater core and evaporator along with the vents. The controller uses electric motors to change the direction of air flow.

the blend door needs repair--need a teardown manual for that mercedes--can be a job even for pros

PULL YOUR CONTROL SECTION FROM INSIDE THE DASH. THE PLASTIC WILL COME OUT WITH A COUPLE OF CLIPS AROUND IT
PLS VOTE!!

your electronic climate controller is bad, and needs to be replaced, it is now running in the default position. Best pace to find one is in a local junkyard or on ebay.

It way be a bad or dirty climate control sensor.

sounds like the resistor, is it climate controlled?

I had the same problem. Push the top right corner of the panel surrounding the LED display hard and see if it works again. If it does, disassemble and the reassemble the panel and it should be working again. It worked for me. I hope this helps.

Yes you car has something like a resistor but its called an ATC BLOWER CONTROL MODULE.Its under the dash on the pass side close to the firewall.

This is obviously a heater system control problem, I beleive this system is vaccuum controled with vacuum acuators that open and close doors in response to the climate control system comands.

Listen for the sound of escaping air from under the dash board, esp on the drivers side. Look for any unattached hoses under the dash. From there if you do not see anything obvious, you will have to obtain a schematic of the HVAC system, understand it's opearation and then start testing the vacuum control devices. maybe more than you want to do.

Goos Luck

you need to replace the blower motor regulator.