I have a 1999 V70. The heating and cooling work but evidently I cannot switch from one to the other. I was told by the previous owner that there are wires that manually switch valves from one to the other. Is this true? And that one of these wires has malfunctioned. To replace the wire the whole dash has to come out. Does this sound reasonable or could there be a more likely reason for the inability to switch from AC to Heat and vice versa?

 

The temp of air out of the vents is controlled by 2 blend doors. (left and right) The doors combine fresh or cooled fresh air with heated air to produce the desired temp. If you don't have climate control (where you set the temp to a number and the system controls the fan speed also) then you have something similar to below - where cables are attached to those arms sticking up and the blend doors are controlled by cables. With ECC there are electric motors that control the blend doors.

Which system do you have and exactly what problem do you have? Blows hot on both sides all the time? With the AC switch on (and the car running) is the freon cold in the system? (the large pipe going back to the compressor will be cold if so, and- careful the small pipe at the compressor will be hot if working normally)

 

Thank you for your question and comment. This is a manual not a climate controlled system. What I was told by the previous owner is that the doors that blend fresh, heat, and cool air can no longer be controlled by the ***** because of a cable problem. My first drive in the vehicle was 2,000 mile trip where I went from Conecticut to Florida and back.in late October. I could feel a little bit of cool air but no heat. So I was fine in Florida, but cold in the other states. I wasn't sure whether the previous owner was told the right diagnoses but from what you said and some other diagrams I've seen I guess it was accurate.

The car is located in Norwalk, CT and I need to find someone to do this for.a sum less than the value of the car.

 

Those cables connect to the levers in the squares below for left and right temp (controlling the blend doors) . Keep in mind the center vents can be simply fresh air from outside.