Hi,

New to the Forum.

Having a strange heating issue with my Superb Mk3.

Get heat in cabin when setting of 24°+ but below that not so just cold air comes in via vents.

Replaced a heater flap motor on passenger side but no joy.

Drivers side one was OK.

Asked my mechanic if he had any suggestions. He says he thinks Mk3s have additional water pumps and they might be the problem. He checked heater matrix and said that was fine.

Just wondering if any one has come across this problem and how to solve it.

Any suggestions much appreciated.

Thanks.

Have you tried the reset of hvac system?

Wwhen it’s done, take care out of auto then set your heat to like 20oC and should feel warmth as long as it’s cold enough outside and inside

Hi Danoid,

Thanks for coming back on this.

I did try HVAC reset with your own video holding down the 2 buttons etc but no joy.

After doing that plus replacing the passenger side heater flap motor which controls cabin temperature apparently with no joy, plus my mechanic saying the heater matrix seems to be working fine leaves me a bit stumped.

Have you heard anything re (extra/auxiliary water pump) causing this issue.

Thanks again for your help and time.

No, the aux heater or pump should help in the initial phases, when the engine is cold, but once you get to temp, then its contribution its marginal.

If you are sure motors/flaps are operating correctly, by manually moving them in all directions, then it could be really the matrix.

A simple test, bring the car to engine operating temp and do a small stretch of road with the car at slow engine speed, and feeling this "coldish" air out of the vents, then without changing anything, increase engine speed - for example, go down 1-2 gears - so that at all other equal conditions, engine has to rev more .... if in that moment you do fee warmer air, then it is the matrix.

Thanks Leolito, will try this over the weekend. Mine is an auto so presumably will have to use the paddle shifts?? Think you are right though that the matrix is the issue. Probably bunged up although I did remove the silica bag from reservoir a while back which was fully in tact but think new non silica reservoir, full coolant flush out and a new heater matrix will hopefully solve the problem. My mechanic is going to love me. Any idea of correct part number for heater matrix on MK3 2.0 Diesel Auto 2016 model. There are so many different types on autodoc etc.

Appreciate your advice and time.

Sorry on weekends I am usually "off" to other engagements ... yes, with the DSG you can go manual and lower the gears used. The idea is that to higher engine speed correspond higher coolant flow and this migh go above the usual "blockade" of a defective heather matrix.

For parts, hope someone else will chime in, and usually yes, heater matrix replacement is a dashboard out job, pretty .... involving ☹️

Hi Leolito,

Just coming back to you re suggestion of dropping gears on motorway with engine at running temp of 90°

Made no difference to temp coming out of dashboard vents.

At 24°+ on heating dial have really hot air but once I dial it down below that no more hot air.

Vents and flaps all working.

Its really strange.

Not sure where it on a Superb but there should be 2 pipes going in through the firewall, feel this when the engine is up to temp and they should both be warm/hot.

Pretty sure that’s a simple way of checking heater core, correct me if I’m wrong anyone.

If all is well there then it could possibly be your actual hvac controls are duff, I’m guessing when you have your controls to 20oC then turn it to 25oC you hear the flap moving?

Just wondering if it’s something simple like that and not sending the correct message, might even be worth removing hvac controls then plug back in and drive the above?

Hi Danoid,

Thanks for this.

Took off HVAC connections as you suggested and put them back on.

They all seemed fine but made no difference to temp issue.

Would there be any chance it would be the Ambient temperature Sensor that is the culprit.

Think I'll order one online.

I can see it behind front Grille.

Any idea how to get at it??

Thanks for your help.

If you have access to some diagnostics, failure of the sensor could be an information you'll get.

Hi Leolito,

Thanks for reply.

Yes my son has a Carly and ran it on my car today.

There was an error in relation to ambient temperature Sensor which got me thinking this could be the cause of my heater issue.

I had a similar situation years ago on a Saab 9 3 and changing the sensor on that actually sorted the problem.

Think it's worth a try to replace it but hoping it does not require front bumper off as that would be beyond me to do.

In Ireland Skoda's key message is that Skoda's are "Simply Clever" so I'm hoping having to take front bumper off to change this sensor is not the only way to do it, as that would not be Clever in any way.

Please tell me it can be done another way.

Thanks. 🙏🙏

Yes, error in the sensor gives you a good way to start.

I do not know where is physically located, but for sure is behind the front bumper, in a place covered from air/wind action.

Rarely is accessible ... we need someone who has done it, search topics of modding/projects in the projects section, there are several cars with the bumper off, as a reference!

Thanks Leolito.

Worth a shot.

Will let you know if I have any success.

TomSko.

I’ll have a look at the repair manual, but not sure when.

If it’s on my downstairs pc I’ll have a look shortly

There’s good news and bad news…

Bad news is official way is to remove the bumper

Good news is when looking at the front of your car, it’s just below the left of your number plate

Top right of my picture is the edge of my front number plate

My fingers are big, not like King Charles’ though and if I wanted to I reckon I could get that off as the grille bits are quite big

As you can see the grey part has some plastic tabs which will need to be pressed in and pull it back I imagine, might be handy to have 4 hands

uhm ... if you can get your hands on some angled pliers, they might to the trick