1999 saab no heat driver side

#9 1 Minute AgoYou don't have to remove the dash. You can get to the broken part from underneath. I ordered a replacement aluminum blend door stop arm to repair the plastic one that breaks and it cleared all the heater problems and codes.Usually it is just the stop arm that broke but sometimes after the stop arm breaks, the shaft can fracture also. In my case, it was just the stop arm.
I originally ordered the stop arm from SAABSite for the left side which I found had broken. It worked but I did have a little trouble getting the new part on. I think most of my difficulty was because the manufacturing of the part from SAABSite was not very good. The hole with the keyways was not round but was uneven and rough. It looked like someone didn't use the right tool to drill it but instead bored it out with too small of a drill bit. I've got a little experience in a machine shop and so I was really surprised/disappointed at this workmanship. I had to clean it up with my tools.
After doing all this, I decided to replace the right side stop arm as well as a precaution. I went on Ebay and found and ordered the same type of part... $32. The Ebay item price was much better due to cheaper shipping which was actually A LOT faster getting to me so a win-win all ways around. I was very happy to find the part from Ebay was much higher quality. That is the one I would recommend if you were to buy. However, I also noticed that the motor shaft on my right side had slipped as you describe. At first I pushed it in too far because when I put the cover back on, it would stall... I found the other end of the shaft that pokes out the back was contacting the cover. I repositioned it again and had no further problems.

This is a problem with the air distribution box behind the dash. Usually a small plastic link that turns the flap breaks. Unfortunately you must remove dashboard and replace the assembly as no repair parts are avail.

You have a broken blend door shaft. The solution is pretty cheap according to the saab services website. This is a very common problem on Saab 9-5s.