Hot air on passenger side. Only cold air on drivers side.

[gidi19]

Hi all.

 

Skoda superb 2.0 TDI 2016 plate.

Has a fault where the driver side does not give out any hot air.

The passenger side and rear heating does.

I've googled the symptoms and the most likely culprit is the silicat bag bursting causing the heater matrix to block.

However I've checked the coolant tank and mine doesn't say silicat on it. The coolant also looks pink. So I'm confused.

I've attached pic of coolant tank.

I've tried doing the reset trick but no luck.

 

[Stonekeeper]

If it has dual zone air con could it not be the temp sensor on the drivers side?

 

 

[gidi19]

I've done a VCDS scan and no error codes are present.

Is it easy to check the temp sensor?

It does have dual air con

[Stonekeeper]

Just done a bit more digging and apparantley if the sensors are faulty it should show up in the vcds.

 

I think they are behind little grills either side of the dashboard but one is difficult to access . I was thinking you could swap them round to see if the problem moved.

 

But then i discovered this which appears to cover all VAG cars

 

People in the comments section of this video say this cured the problem you describe?

 

 

 

 

Similar thread

 

Edited 18 April by Stonekeeper

[gidi19]

Hi,

I've tried the above procedure. Did not work for me.

Gut feeling is having to replace the heater matrix, but people are saying it will cost in the region of £1000.

I've changed a heater matrix before on my octavia mk 2 so do have some experience. 

Only thing that i'm still trying to figure out is how to take the glove box off without removing the infotainment.

 

[Danoid]

Your header tank doesn’t say mit silikat on the header tank which normally means you’re good.

 

Might be better to disconnect the header tank and look with a torch if it’s got the bag, then your suspicions could be true. Saves doing matrix if it’s not actually required

[nicknorman]

Is there actually a different matrix for LH and RH sides? I wouldn't have thought so. I would expect there to be one source of hot air that is then mixed with cold air with valves to get the right temperatures in the various zones.  Could it not be the temperature control flap sticking on that side, or the motor defunct?

[Stonekeeper]

I think the air con components are between the Heater matrix and the blower system and that has the ability to adjust temperature to either side.

[gidi19]

I thought the flap motor might be an issue so I looked underneath the steering wheel and I could see the motor flap.

I then turned the heating from hot to cold and could see and feel the motor moving up and down. So definately isn't the motor being stuck.

[gidi19]

Does anyone know how to access the interior temperature sensor on the driver side? I want to check that before replacing heater matrix

[gidi19]

VCDS showing the following

 

As a test I took the plastic spigit thing out and tried opening anb closing the flap manually. I can close and open the inside airvent so the flap motor is definitely working.

That leaves me with checking the interior temp sensor. But the videos I've seen indicate if the temp sensor was malfunctioning then it would be at a higher degrees and the car would compensate but glowing cold air out on one side. This does not seem to apply here as it is correctly showing that it is blowing out cold air.

Is there anything glaring I'm missing the the VCDS pic.

Next step is going to be to try doing a coolant flush and maybe try flush the heater matrix out, depending on how easy it is to access from the engine bay.

There seems to be a lot of guides on Octavias, but not many ok Superbs. 

 

[Danoid]

10oC is a big difference.

 

Have you tried a recalibration using vcds? I know you done the trick holding buttons down but wondering if it’s best to do it via vcds then recheck.

 

I’d still get the header tank off as well

 

Also is this a new to you car or has the problem gradually got worse?

[gidi19]

Hi,

 

This is a new car I bought. So I don't know the history behind it. Was bought from Auction with no known faults.  No point trying to get anything from auction place

 

What do you mean by take the header tank of? Is this to check if it has any air trapped in the system. I'm planning on doing a partial flush on it tomorrow, see if it helps.

 

I'll try re-calibrating with VCDS

 

[Danoid]

If you follow that, once the header tank is off shine a light and look to see if there’s a silicone bag.

 

Sometimes they are inside, some times in the walls.

 

I must admit the picture you posted looks like the coolant is incredibly dirty, but might just be the picture.

 

The silicone bag splitting is incredibly rare to be honest, but when it does go it can clog the matrix.

 

I guess the reason why the car was auctioned in the first place is because of issues.

 

also what colour is the coolant? If it’s bright pink that’s good, if it’s brown that could indicate the header tank was replaced with a non mit silikat version and coolant never flushed out, because mixing g13 with g12evo makes the coolant brown

[gidi19]

Just an update.

Had a look inside the header tank and even though coolant was pink,it was full of gunk. So I took the header tank out. Started to wash it under the sink and half hour later there was still gunk coming out.

At this point I can say that most probably the whole system is contaminated and full of corrosion.

I gave it a partial flush and tried cleaning out as much out as possible.

Plan going forward is to give it a flush everyday for a week,trying to remove as much gunk as possible. And when it seems like it's improved to replace the heater matrix.

Some points if anyone can help.

I've read putting in wymms cleaner to try clean the corrosion out helps?

Is it worth replacing the radiator?

Best way to clean the heater matrix pipes? I've seen videos of people just sticking a water hose and flushing it out.

Any other advice would be appreciated.

 

Thanks

 

[gidi19]

Hi all,

 

Could really do with some help.

Tried to flush the system out again today. unfortunately there is a leak on one of the intercooler/radiator hoses. Upon a closer look it seems like I might have lost the rubber seal, if one existed. Or the current seal is no longer working. I've tried for an hour to try sort it out, but have had no luck.

Does anyone know if the larger intercooler/radiator hose has a seal/gasket and if so where can I source one. Going to try ring TPS tomorrow and see if one is available.

 

Edited 22 April by gidi19

[gidi19]

The third pic is what came out the pipe.

It wont stop leaking

[gidi19]

Here's two more pics of inside of the pipe

[gidi19]

Figured it out,

 

 N90765301

 

O ring must have fell out. Above is the part number for anyone who needs it

 

[gidi19]

Hi all.

 

Just an update.

Changing the heater matrix was a very fiddly job,but finally succeeded and happy to say heat has returned to both sides. 

Also had an issue with the ACC and on inspection turned out to be a broken bracket. Replaced the bracket and initially was throwing an incorrect position sensor code but driving to work and back it suddenly sorted it self out.

Next job to give it a service and maybe attempt to replace the gearbox oil.