Saab Frequently Asked Questions
Special Thanks to Fred Frigo for the contribution of most of this information. It is guys like Fred that help keep our Saabs rolling along. Kudos to Fred!
A number of problems can be encountered with the manual controls for heating and cooling in the Saab 900 and 93. In some cases, it is possible to replace individual components of the manual heating and cooling control assembly. If the control knobs are defective, they simply pull out and can be replaced with new knobs (Saab Part Number 5331665).
If the air flow position control knob is not functional, and the control knob seems to turn too easily, it is likely that the plastic shaft that looks like a "toilet paper holder" (Saab Part Number 4364279) and provides linkage from the dash control to the heater box is defective.
Toilet Paper Roll
The cabin air-flow control shaft can be replaced by removing the console panel on the passenger side. Once access to behind the dash is available, the white plastic linkage connecting the manual control to the heater box can be disconnected. With your fingers, gently slide the linkage back (approx 1.5 cm) to separate it from the manual control shaft. Once the linkage has been disconnected, the manual heating and cooling control assembly can be pushed out of the dash. Use a flat blade screw driver to gently pry the white plastic locking tabs up on the bottom of each side of the assembly as you work it out.
It may be necessary to remove cables connected to the manual heating and cooling control assembly to move it out far enough. The cables are keyed, so the pins of the connectors must be aligned properly before they can be reconnected. The cables also have locking mechanisms to prevent them from coming loose. To unlock, gently pry out the purple tabs. These tabs should be pushed in to lock the connector in place when the cables are re-installed.
With the manual heating and cooling control assembly pushed out from the dash, access the cabin air-flow control shaft to replace it through the front hole in the dash. Make note of the position of the defective shaft, so that the new shaft can be lined up in a similar fashion. With your hands pull the old shaft out to remove it. Installing the new shaft is more challenging. Holding the tip of the shaft, guide it with your fingers as close to the heater box as possible. It should snap into place with little force. After it installs into place, re-install the manual control assembly by pushing it into the dash until it snaps into place. Re-install the linkage shaft to the control knob, then re-install the console panel.