Not sure if that is all caused by the aftermarket radio install... which was a bit sloppy, if you ask me.
Here is the screen shot from Durametric.
Symptoms: no heat although the heater core is hot. Error 26 Mixing flap motor fault
While researching it, I confirmed the fresh air/recirculation flap does not actuate either.
What works?
Basically everything else is fine.
I can change the temperature, adjust the blower, change direction of the air. It also works fine in automatic mode.
I also have the foam flying around. I know this one and solution for it. I will get to it eventually.
So, my work around during 15 hours drive in cold weather, where 6 were in rain, and another 3 in snow.
I managed to squeeze my hands under the flap motor and disconnected the arm from the flap.
The flap dropped automatically to the hot position. I could easily move it, so I know it has free movement.
Heat started blowing right away and I could continue my journey.
Anyway, what we could do here? What am I looking at?
Also, would the system be in German language?
It shows F for temp, but MANUELL for manual operation mode. Not sure if it has any significance here.
This is one I am not sure how to bite. Not only poor access, but some wiring messed up from the radio install.