C4 VTS - Air recirculation does not work

[lancia58]

Hi

The Air recirculation ( climate control ) in my Citroen C4 VTS doesn't work. I removed the glove box detached the servo motor that moves the flap and saw that when the recirculation button is pressed the motor rotates but for a short way. As I have spare servo motor I did this test with several motors and they all rotates a bit. It looks that something in the control circuit is wrong. BTW it also happens on my other C4 ( 4 doors ) with climate control

Thanks

[GiveMeABreak]

So what makes you think it isn't working as a matter of interest?

[lancia58]

When the glove box was removed I pressed the recirculation button and the flap didn't move, on top of it when the entry of air from outside
is blocked off the air stream should be stronger ( one can hear it ) but it doesn't happen. . I have 3 C4 and with one off them ( with no climate control ) when the entry of air from outside
is blocked off the air stream is intensified .

[GiveMeABreak]

I think you'll find that is by design:

The system uses a Partial Air Recirculation
The partial air recirculation consists of using (via the air conditioning unit air intake flap) part passenger compartment air and part exterior air. For all engines, a partial recirculation phase is carried out to improve the heating of the passenger compartment.

This recirculation phase takes place during the engine coolant temperature increase between 35°C and 65°C. In the same way, total or partial air recirculation is carried out to improve the performance of the air conditioning. The rate of air recirculation depends on the exterior temperature and the calculated passenger compartment temperature.

This will explain why the flap is only partially moving.

[Cutac]

But it should move fully. I've been behind the glovebox recently and there's a tube which consists of two parts that open or close whether recirculation is selected or not.

[GiveMeABreak]

Yes but which one are you talking about - there may be both air mixer flaps and air distribution flaps.....

[Cutac]

First picture, part 2 moves IIRC.

[GiveMeABreak]

This is as far as I can tell - there was a changeover in the system up to build date 10739 and the new system from 10740. Your build date is 10728 so uses the older system.

The Diagram Showing the same (Stars Show the Other Units)	This shows the mixer unit in place as per my last picture in the previous post. So not sure if that is one of the ones in your picture or an additional one!

[Cutac]

What's the difference with the new system?

"This shows the mixer unit in place as per my last picture in the previous post.
So not sure if that is one of the ones in your picture or an additional one!"

I'm pretty sure that's the same one from my photo. Bottom to top, temperature motor(a gear on the axle), direction motor(a hexagon on the axle) and recirculation motor(didn't take it off).

[xantia_v6]

Can you exercise the actuators with Diagbox? I don't think that the recirculation flap normally opens more than 20% in automatic mode.

[Cutac]

Even if I could, I can't see it with the glovebox in place and it's quite an exercise getting it out.
When I was trying it I wasn't using auto mode, I was manually changing the settings to see what'll happen/move.