Hi.  I have a 2017 S5 where overall I've had no real problems since getting it last year.  That being said, just now I put the heating on and it seems to only blow tepid despite it being cranked up to the highest setting. I've turned the sync settings on and off for the passenger side and rear however it still blows tepid or freezing cold if the air con is on. 

Any help on this would be greatly appreciated.

 

John

I'd recommend a diagnostic check to see if any fault codes flag up as it could be an issue with the heater control unit. However, does the engine get up to temperature ok? As I believe a failing thermostat can cause similar problems. 

If I understand your post correctly, they other vents blow hot and cold air (depending on the temp setting on the climate control) but the driver's side is stuck on low?

 

If so, I had the same problem.

The problem is a motor that's bolted on the heater core (behind the centre console, on the driver's side) has failed.

This motor controls a plastic arm that move the flap controlling the flow of hot air to the vent (there are 3 motors that control the temp for the various vents independently).

The part itself cost around £170 (part is 'V159 control motor' for the driver side).

Labour was around 2.5 hours.

It cost me around £450 in total to fix it.

 

You will need to find a garage that has the Vag.com or VCDS software though, as they need to perform a 'basic setting' on the part to sync it to the system. A decent VAG specialist garage should have this software.

Technically, the whole dash is supposed to come out to reach the part (going by the book), but a mechanic can get away with removing just the lower part of the drivers side dash and get enough space to replace the part (it's a tight fit though).

There is a good video guide on youtube is you search for it.

Hello hope you are well

 

Ive developed the same problem and im trying to find a good video on youtube to see how to do it but with no luck would you be able to send me a link or tell me what you searched when you get a chance ? 

thank you 

On 9/23/2022 at 6:20 PM, kh904 said:

If I understand your post correctly, they other vents blow hot and cold air (depending on the temp setting on the climate control) but the driver's side is stuck on low?

 

If so, I had the same problem.

The problem is a motor that's bolted on the heater core (behind the centre console, on the driver's side) has failed.

This motor controls a plastic arm that move the flap controlling the flow of hot air to the vent (there are 3 motors that control the temp for the various vents independently).

The part itself cost around £170 (part is 'V159 control motor' for the driver side).

Labour was around 2.5 hours.

It cost me around £450 in total to fix it.

 

You will need to find a garage that has the Vag.com or VCDS software though, as they need to perform a 'basic setting' on the part to sync it to the system. A decent VAG specialist garage should have this software.

Technically, the whole dash is supposed to come out to reach the part (going by the book), but a mechanic can get away with removing just the lower part of the drivers side dash and get enough space to replace the part (it's a tight fit though).

There is a good video guide on youtube is you search for it.

Hello hope you are well

 

Ive developed the same problem and im trying to find a good video on youtube to see how to do it but with no luck would you be able to send me a link or tell me what you searched when you get a chance ? 

thank you 

Hi mate,

 

Here's a video:

This one shows the passenger side which is much easier to repair as there's much better access to the control motors, so it's not much help. I'm trying to find the video for the drivers side replacement (for the V159 motor), but no luck finding it yet.

 

Exact same problem for me.  Cold on Driver side.  A5 S Line 2017.

Been quoted 800 quid from an Audi Specialist/Independent. Dash out job.

I was looking for a manual reset/recalibration sequence you can try with the panel/buttons but I can't seem to find any info on it?  

Officially going by the book, the dash has to come out, but it can be done without it!!!

There is a youtube video of someone replacing the flap motor by removing just the lower part of the dash and the side of the side console.

It's a bit awkward to bend down and get access but it can be done. I think there is another flap motor that needs to be removed before you can get access to the other flap motor.

I showed my Audi specialist the video and he managed to do it.

I think it cost around £450 all in. The genuine Audi part was around £100, but i'm sure you can get a cheaper copy part.

I don't think you can recalibrate the part via a panel button sequence. You need an OBD2 scanner that has the 'Basic Reset' function to do this.

Edited November 14, 2025Nov 14 by kh904

After the diagnostic there were 10 errors that came up 

Is this normal for when one motor fails or does this point to an underlying electrical fault?  Bit concerned that the Garage doesn't really seem to know!

I'm surprised that so many of the flap motors are showing mechanical faults!!!

The mechanic should clear all the faults and then drive the car for a bit, try all the air-con/climate control settings and see if the errors reappear!

If the faults do reappear, then maybe another specialist maybe able to assist