Technical Air Vent Selector for heating not working

[M5 FHB]

Hi all, i have a 2022 Fiat Ducato Dethleff Trend Motorhome.

The heaters are working all fine, but the selector control won’t switch to different vents, ie we can only get the heater to blow straight out the front vents, it won’t for instance blow at the wind screen or both etc. I’ve remove the dash in part , everything seems to work including the heater panel etc, checked all the forums and there lots of talk about the heating settings not working but nothing i can find talks about my issues with the selector not going between the different vent settings.

Has anyone had this fault and able to offer any advise as we keep getting steamed up windscreen but can’t get the air to blow at it.

 

[rayc]

I think the vents are operated by a cable from the back of the switch to the vent lever on the heater matrix box. an example of the switch panel linked below. I guess you need to ascertain if the cable is moving when you turn the control and if so what is happening at the heater box.

FIAT Ducato 250 Heater Control Panel 168340200 | eBay

Manufacturer Part Number: 168340200. Vehicle/Model: FIAT Ducato 35 Multijet Iii. Interior Trim Colour: Not Available. Bodywork Colour: WHITE. Interior Fabric Colour: Not Available. Paint can age differently due to factors such as storage, usage, UV exposure etc.

www.ebay.co.uk

 

[M5 FHB]

I think the vents are operated by a cable from the back of the switch to the vent lever on the heater matrix box. an example of the switch panel linked below. I guess you need to ascertain if the cable is moving when you turn the control and if so what is happening at the heater box.

FIAT Ducato 250 Heater Control Panel 168340200 | eBay

Manufacturer Part Number: 168340200. Vehicle/Model: FIAT Ducato 35 Multijet Iii. Interior Trim Colour: Not Available. Bodywork Colour: WHITE. Interior Fabric Colour: Not Available. Paint can age differently due to factors such as storage, usage, UV exposure etc.

www.ebay.co.uk

Hi Rayc, i can see the white cable moving when i turn the seclector but just can’t see to where the cable goes to, i think whatever it connects to is the problem but i just don’t know where to start. I have taken a lot of the dash out, but stopped as it looked as if i would tave to remove the entire dash to get to the end of the cable.

 

[rayc]

Hi Rayc, i can see the white cable moving when i turn the seclector but just can’t see to where the cable goes to, i think whatever it connects to is the problem but i just don’t know where to start. I have taken a lot of the dash out, but stopped as it looked as if i would tave to remove the entire dash to get to the end of the cable.

It should go to the air distribution part of the heater box assembly.

 

[rayc]

found this photo on the web of the switch panel to heater cable connections. If you listen carefully can you hear any movement from the box when the control is turned and white cable inner wire moves ? PS I think the green cable is the external / recirculating air inlet control which is connected to the air inlet from the bonnet scoop. I cannot guarantee that a 2022 model is exactly the same as this one which is a few years earlier

 

[M5 FHB]

found this photo on the web of the switch panel to heater cable connections. If you listen carefully can you hear any movement from the box when the control is turned and white cable inner wire moves ? PS I think the green cable is the external / recirculating air inlet control which is connected to the air inlet from the bonnet scoop. I cannot guarantee that a 2022 model is exactly the same as this one which is a few years earlier

Hi Rayc, so the green cable does go to the recirculation as i can see it operate and work just fine. So it’s all about the white cable which i can only assume is the problem. I can only assume that to get to the end of this i have to completely remove the dash board?

 

[rayc]

Hi Rayc, so the green cable does go to the recirculation as i can see it operate and work just fine. So it’s all about the white cable which i can only assume is the problem. I can only assume that to get to the end of this i have to completely remove the dash board?

I don't know is the short answer. Before undertaking any work are you sure the white inner cable is moving in response to switching between the various selection positions? I wonder removing if the glove box or internal compartment of the dash drinks bin would allow access??

 

[M5 FHB]

Hi Rayc, the white cable moved from the back of the control panel with the cable pulling, but it’s were it’s connected to which the heater box in the photo above. So what needs removing to get to the location where the cable connects to the heater box.

 

[rayc]

Hi Rayc, the white cable moved from the back of the control panel with the cable pulling, but it’s were it’s connected to which the heater box in the photo above. So what needs removing to get to the location where the cable connects to the heater box.

Sorry I have never stripped one down but these people have removed the complete heater box