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After removing the upper blend door motor, I found a few teeth were missing from the motor gears -so at first thought that was the problem. Attempting to rotate the door with a screwdriver only allowed a few degrees of movement and I could also hear something rattling around in there, so the issue was more than a motor problem.
What had happened was one of the defrost flaps had broken off it’s mount and fallen into the CCU, jamming the blend door in the process.
In order to try and get a better look at what was going on I removed the centre vent and pushed the vacuum flap open. When I shone a flashlight into the cavity I could see part of the broken defrost flap poking up from inside the blend door area of the CCU.
Wedging open the vacuum centre vent aperture, I could reach through with my long needle-nose pliers and grab the defrost flap. Although I could wiggle it a bit, there was not enough room to pull it out.
As I had hold of it, even though I couldn’t do much more than move it side to side, there was no bloody way I was going to take the dash out to get it. I looked at the vacuum centre vent flap supports. The flap stops had two thin plastic uprights and a 4" centre section that the actuator sat on. Apart from these pieces in the centre, the flap also homed on all four sides of the aperture.
So I decided to cut away the centre pieces with a hacksaw blade. After removing the pieces of plastic there was now a slot about the size of a letterbox. I reached in with my needle-nose pliers, shifted the broken flap to the left until I could see the end, grabbed it and removed it from the CCU.
The centre vent vacuum door still seemed to have plenty of support around the perimeter when it closed so I didn’t bother gluing the pieces back in.
Tested the movement of the upper blend door and all good. I had a spare motor so fitted that and put everything back together.
On the drive home, tested the climate control and everything worked properly, at least I could get heat or cold to the upper vents.
Not sure what will be the effect of the missing defrost flap will be, but for sure it hadn’t been doing it’s job for quite some time stuck inside the CCU!