[Steve F]

Hi
The cooler nights are upon us now and when driving last night I turned up the AC to 25 and cold air still blew out of the driver side vents. Hot air came out of the passenger side though.
The fans are working and air is coming out of all vents.

???? Is this likely to be a blow fuse or something like that ?

 

[SQ5_NW]

Could be the sensors fitted on the ducts behind each of the vents. If you can pull out the vents, try swapping them from the side that is working and see if that switches things around (warm air drivers side, cold air passenger side).
Passenger side can possibly accessed by removing the glovebox, not sure about drivers side.

The part number could be 3D0907543A (such as eBay listing 134158130985)

 

[SQ-Raphster]

Before you go and do anything complicated - do you have dual or 3 zone climate control? If so are the temperatures synced on both sides?

 

[Airhog]

I have got exactly the same problem with my 2018 3.0 litre Q5 on the same side. Mines 3 zone climate and I’ve tried matching temperature, varying temperature between sides but just get the same cold temperature on the drivers side no matter what the temperature is set to or the vent position. Carista says there is an error in the system but the code number just says heating fault. I have read that the control arm for the heater sometimes needs re syncing or that the arm sometimes breaks but I’m lead to believe that this controls where the air goes not the temperature

 

[Airhog]

this video may help

 

[lsumharper]

New owner of '18 Q5 (have had '14 A4 before)... Ran into same issue. Is this an at home or a dealer fix?

 

[Steve F]

New owner of '18 Q5 (have had '14 A4 before)... Ran into same issue. Is this an at home or a dealer fix?

I fixed it myself in the end. I tbink it was a physical obstruction somewhere in the system.
I closed all the vents that were blowing hot and pushed the fans up to max to blow through the vents that were blowing cool, closing some of those too so that all the air was forced through the central vent on the drivers side.
After maybe a minute it started to blow warm and it’s been ok since.

 

[lsumharper]

Go figure. Will try this afternoon. I live in Florida so this is a one week a year we need heat

 

[Steve B]

I have 3 zone climate, my issue is the rear vents are always blowing cold air no matter what I set the scroll temp too and even when its set to auto...

 

[lsumharper]

Go figure. Will try this afternoon. I live in Florida so this is a one week a year we need heat

no dice…. Maybe the thermostat.

 

[Airhog]

Hi, I’ve not sorted mine out yet but wondered if anyone else had resolved this yet? Thanks