In continuance of my a.c. rebuild saga I now believe to have failing A.C. Blend Doors. If I set the climate control on low then disengage the a.c. the vent temperature climbs to 140F. Making me believe the blend door is open on the heater side. I have replaced the condenser, expansion valve and compressor and have the appropriate refrigerant in the system and low & high side pressures seem to be within spec. With the A.C. engaged in climate control the vent does cool but not enough especially at idle. Dealing with this car in this Texas heat is no joke.

Anyone know how to diagnose and or calibrate the blend doors via SDD? Also where can I source replacement blend door actuators?

 

Hi BlackKat

Actuators can be bought on e bay, I have a spare and I think that they are all the the same but

the mechanism between the motor and the door is different.

There is a fault on a blend door on our Passat because I can hear it clicking and when my

son put his scanner on it he got a DTC for a blend door which rather surprised me.

I have given up with SDD after two faulty clones.

The only way I can think of is to remove the glove box and watch the actuators while

someone presses buttons but there are some on the other side of the box also.

 

Thanks Meirion1!
I was going through the electrical workshop manual and found the instructions for blend door actuator removal.
Anyone happen to have a diagram identifying the different actuators on the evaporator housing?
Also anyone know how to manually move the blend door to test?
Thanks!

 

Hi there sorry to boder but did you fix your issue with the ac blend door thing.... I have some issues with the driver side not cooling only the passenger... Is there a way to manually move the blend door some how... Thanks Much..

 

Sorry, I took my box apart and turns out my blend doors opened fine. All I did at that point was to replace the foam on the doors.
You can see from my pics attached where the actuators are located on each side of the box and what they control. You may have to remove the dash like I did to access some of these.

 

Wow what a job!

I have never seen those innards before and have been reading this forum for years.

Thanks

Where was the fault?