Even with engine fully warmed up to normal running temp I have cold air coming into the car.

I tried blasting it up the motorway with the internal temperature knob turned up to Max (29 Deg C) on both sides and it got slightly better.

There is plenty of coolant in the engine.

I am suspecting an air lock. How else to clear it?

Andrew

Have you tried resetting the climatronic control flaps? If not press and hold the A/C and face level vent buttons 5ogether for a few seconds and that should attempt to reset their positions and may help.

Thanks Skomaz. I will try that today and report back.

@skomaz sorry for delayed feedback but I did not till now have a long enough journey to test your suggestion with a properly heated up engine. Results:-

1, Got the two suggested buttons flashing alternately but no change in heat output to my feet

2. Tried full fan and max temp again. No joy.

3. Switched off Climatronic control. Likewise

4. Tried all the heating buttons one by one at full blast

5. There is warmth in the heater unit but it does not feel to me that there is much hot air coming down above the ankles

Any further suggestions gratefully received...

Hi, welcome.

Shomaz has already suggested the first thing I'd suggest with one of those Climatronic type heaters, next would be to put a VW appropriate scan tool on. To avoid spurious reports this needs a fully up to date program on it suitable to your model and (part) year (or VIN), the battery for the scan tool (if appropriate) and car's 12v battery in good state(s) of charge.

This is the 'Hellos and Goodbyes' section so less traffic here and not specific to model so you would be better looking in and/or asking in the 'Skoda Kodiaq MK1 (2017-2023)' for information and advice from the model owners and others.

HTH.

'Skoda Kodiaq MK1 (2017-2023)' forum. - https://www.briskoda.net/forums/forum/339-skoda-kodiaq-mk1-2017-2023/

Hi Nigel

I am not at all sure how my post ended up in 'Hellos and Goodbyes' but perhaps the Moderator can move the whole thread for me?

As to the car there don't appear to be any relevant codes showing up on my AutoPhix 7610 scanner which I updated at your suggestion first.

I did however, again try the fan on full blast and changed from External to Recycled air and there soes seem to be a bit more air coming through.

Does anyone know where I can find a definitive explanation of all the Skoda Kodiaq codes?

There are codes showing on the scan but none of them seems relevant - except possibly this one. (see photo). Anyone know what "not authorised" means?

2 hours ago, andrewclark55 said:

Hi Nigel

I am not at all sure how my post ended up in 'Hellos and Goodbyes' but perhaps the Moderator can move the whole thread for me?

I'll put in a Report (three dots top right of post(s), drop down menu) asking for a Moderator to move it for you. ETA: done - tick

2 hours ago, andrewclark55 said:

As to the car there don't appear to be any relevant codes showing up on my AutoPhix 7610 scanner which I updated at your suggestion first.

Potentially all codes might be relevant and some or all can be unexpectedly related. Error codes can be from low state of battery charge (car, scanner), disconnection/change of battery, change of car part(s), 'coding' programming errors or incidents, computer brain-farts car or scanner programs, perhaps low battery in proximity remote(s) (never have a "spare" key have all keys used in some sort of alternate rotation use).

2 hours ago, andrewclark55 said:

There are codes showing on the scan but none of them seems relevant - except possibly this one. (see photo). Anyone know what "not authorised" means?

See my answer above and look up B104A00 on the web again bearing in mind my answer above.

2 hours ago, andrewclark55 said:

I did however, again try the fan on full blast and changed from External to Recycled air and there soes seem to be a bit more air coming through.

The hot air isn't coming in from outside but that means you are also not getting fresh air in the car just recirculating what's there which is OK for short periods but not longer periods, probably has something about this in the car's 'Owner's Manual'.

Have you have the coolant level checked to see if it's low, possible leak, might be lack of maintenance but some get away with that longer than others or a faulty or break somewhere.

Good luck.

Edited 22 June, 202522 Jun by nta16
ETA

Hi Nigel

//The hot air isn't coming in from outside but that means you are also not getting fresh air in the car just recirculating what's there which is OK for short periods but not longer periods, probably has something about this in the car's 'Owner's Manual'.

Yes I know that but flipping from one mode to the other opens and closes flaps and seems yo have got air flowing again.

//Have you have the coolant level checked to see if it's low, possible leak, might be lack of maintenance but some get away with that longer than others or a faulty or break somewhere.

Yes. as per my original post it was the first thing that i checked.

Will do some more testing and see if my random trial and error approach has done anything!

I believe that fault code is usually associated with a key coding issue or immobilizer issue. I'd be tempted to clear it and see if it comes back.

I'd also do a few cycles of the flap reset just to see if that helps.

Hows the car engine temperature? Ok on a run or varying?

Finally check the coolant header tank... Is it a 'mit silikat' one with the silicon bag in it ( I can't remember if the 2.0 tsi originally had one or not ). If it did and it's split that can cause the heater matrix to block.

Hi Skomaz

>I believe that fault code is usually associated with a key coding issue or immobilizer issue. I'd be tempted to clear it and see if it comes back.

That could be the case as my key battery went flat recently. I'll try clearing the code as you suggest as there is also a separate warning about that.

>I'd also do a few cycles of the flap reset just to see if that helps.

Yep!

>Hows the car engine temperature? Ok on a run or varying?

Steady as usual at 90deg (12 o'clock). Rock solid.

>Finally check the coolant header tank... Is it a 'mit silikat' one with the silicon bag in it ( I can't remember if the 2.0 tsi originally had one or not ). If it did and it's split that can cause the heater matrix to block.

It is just a normal plastic tank on this one. Usually half-full when hot. Releasing the pressure cap slightly when hot caused it to rise to nearly overflow, which is why I wondered if there might be air in the coolant locked in somewhere...?

Get the gearbox thermostat changed (yes, gearbox). Thei fail very often. Doesn`t cost much.

@linni

>Get the gearbox thermostat changed (yes, gearbox). Thei fail very often. Doesn`t cost much.

You have me puzzled now!

I this in response to the DTC code I posted?

4 minutes ago, andrewclark55 said:

@linni

>Get the gearbox thermostat changed (yes, gearbox). Thei fail very often. Doesn`t cost much.

You have me puzzled now!

I this in response to the DTC code I posted?

No, just personal experience.

Not sure it will help but worth to try.

@linni Sorry - do you mean in respect of my original heater problem?

Yes, when thermostat fails, it will not blow hot air anymore. Occasionally may, but most time not.

2 minutes ago, linni said:

Yes, when thermostat fails, it will not blow hot air anymore. Occasionally may, but most time not.

Interesting! How the heck did you figure that one out?

Is it sarcasm or for real?

Not being sarcastic at all. Being an engineer I don't know why the heater would have any connection with the gearbox. Can you kindly explain the logic of what you have discovered!

That`s german logic :) Kodiaq has 3 thermostats and the gearbox one fails often. I do not know the exact circuit of coolant but it`s for sure the gearbox thermostat affects all the circuit. Including the cabin heating.

@linni Thanks. I will clear all the codes and then if the problem still persists will check that one out.

6 hours ago, andrewclark55 said:

Yes I know that but flipping from one mode to the other opens and closes flaps and seems yo have got air flowing again.

Which may suggest there is a problem with the flap control (computer) or just mechanical restriction - this may not be the only issues at play though, but not helping the situation.

6 hours ago, andrewclark55 said:

Yes. as per my original post it was the first thing that i checked.

Sorry my mistake I meant air-con refrigerant rather than engine coolant (perhaps you did too and have already checked for refrigerant leaks).

3 hours ago, andrewclark55 said:

Steady as usual at 90deg (12 o'clock). Rock solid.

The dial are designed that way to give reassurance to drivers, the dials are bias to show 90 even though in reality the actual temperature could be a reasonable margin either side of 90 and moving up and down from 90 but the upper margin will be well within normal range of coolant temperature. Obviously you want the coolant temperature to remain around the normal operating temperatures as much and often as possible but you can run up to the red section on the gauge just not a great idea as it leaves less margin to full overheating but there will be bells and whistles and restriction before this point unless there's a real big failure on something somewhere.

Andrew as you're not the usual stereotype of an engineer (just been posting with a young version) and willing to listen to others that aren't engineers (well I'm not anyway) I'll be a bit more direct with you.

I put about batteries and had in mind remote batteries (I see I've already put about never having a "spare" key) based on your code but I have no idea how good or accurate your Autophix is. All scan tools have strengths and weaknesses and you are using their sets of computer programs in conjunction with VW's very complex, very intertwined computer programs and as you know the engineers in both of these will have some errors. omissions and compromises, then you add in the external electronics, electrics, mechanical. This means things are not always black and white, the scan tool reporting has to be confirmed, checked, cross referenced. In other words the computer ain't always right and when it is then mostly it is just a signpost to the direction of travel for further diagnosis using other diagnostics tools including your human senses.

With any car problems particularly modern complex ones like the German marques have made for many decades you need to consider the problem may be caused or affected by more than one issue and solving one problem may not solve all.

If you research you will find things like a car's computer systems thinking there might be a fault with a brake light causing other unexpected problems like putting the car into limp mode and even more less relatable issues.

One electric/electronic issues can back feed and scatter to other areas of the car where the systems there can throw wobbles, it's Y2K panic again, low 12V battery state of charge can throw up all sorts of unexpected VW warnings, error codes and issues, the headlights might seem bright enough and engine easily start but the car's computer systems won't be happy. There are loads of threads and posts with this in the various forums about this (yet some still find it difficult to accept and make the situation worse by not recharging the 12v battery).

This is why I personally (not an engineer in computers or anything else, or expert in anything) prefer that a report of all error codes is taken and recorded but then all error codes are deleted.

If you were to put different scan tools on your car they may give different readings and your car may report different error codes at different times using different scan tools or the same scan tool every time - it's a hypochondriacs nightmare (or dream) scenario. 😄

Don't put all your faith in (so-called) "smart" devices or computers generally, as you probably know they're not at all smart but extremely, extremely dumb, even AI always confirm, double/treble check and cross reference the information they give - and any information from any source including blokes off the internet and even manufacturers databases (good engineering practice I believe, though hard to imagine with some of the stereotypical engineers I know, meet and dealt/deal with).

There are Briskoda members with VCDS and other scanners that offer help (reports, clear codes and more) mostly non-professional, it might be useful to get a second scanner to confirm your Autophix** also VW specific with access to more data to get a better overall picture plus perhaps live data. See the following link for those in your area who may be able to help if you want. - https://www.briskoda.net/forums/topic/262215-list-of-vcds-owners-previously-known-as-vag-com-vcp-owners/#comment-3091029

** I see Autophix 7610 is VW specific (USA lead possibly by the I/M).

Edited 23 June, 202523 Jun by nta16
ETA: missing link and 7610 VW

For quoting from previous posts, if you want to, you can highlight the section you want then you should see just below the end of the section a black box with open quotation marks and the text quote selection which if you click-on (touch?) that black box then puts it as a quote into the post you are writing.

@nta16 Thanks very much Nigel for your very full and detailed information.

I'm an old-school engineer and understand fully that it needs knowledge and understanding of the systems we work on to diagnose issues. In short, you have to first know how it is supposed to work before understanding why it it isn't working.

And yes, there is far too much reliance on computer diagnosis by younger apprentices unless they refer the results to someone experienced in that particular engine or subsystem who just knows what is likely to have gone wrong with it! But these auto systems are, as you say, complex and components interrelated enough to completely mislead. For example my Son's Octavia VRS recently showed up with both a tyre pressure warning and an ABS fault. He was quite alarmed by these until I pointed out that there was also a wheel sensor fault code and both systems rely on the same sensor. We got the sensor changed and both faults were fixed immediately.

So to your point about refrigerant I DID actually mean engine coolant as that is what heats up the radiator within the heating system. In this case we are talking of a lack of hot air flow into the driver's feet, not an air-conditioning problem so I'm fairly sure we don't need to go there. It does seem likely that one of the flaps is stuck hence my blast-the-hell out of it strategy with the fan on full power, and the temperature turned right up.

I will need to drive it a bit further to see if we have achieved any improvement, but meantime thanks to you and everyone else who has thrown their hat in the ring :).

Regards

Andrew

Edited 23 June, 202523 Jun by andrewclark55

Hi Andrew, thanks I do tend to be long-winded in my posts and often very long winded and as I'm not into serving everything up on a plate (arse-wiping the young) so that things can be learnt and confirmed, mainly because I don't know the answer(s) and some (many) times the answers can't be know by anyone on the limited information in a post or posts unless many more questions and answers are asked which many here don't like and don't think is necessary. The Twitter/X style of here's a quick short question with no further information and a quick, brief, instant resolution is expected to be given, and perhaps sometimes this is possible but having dealt with people of all sorts and those with old cars ownership when assume is used, well you probably know the saying.

The problem with knowledge is that it changes with time and to what depth this knowledge is actually needed, yeap it's best to know why but it must also be accepted that sometimes no one knows and sometimes those that think they do are just wrong for many reasons.

I'm old-school-truant, learn a little by experience, if I can remember and hold the experience, increasingly more difficult with age for many reasons. Your son's sensor is a good example, a common problem with a common solution and I would guess (and hope) you tested the sensor before replacing it. Obviously mechanics (and engineers) don't too readily want to admit that a lot of car servicing (in the more historical rather than VW terminology sense) and maintenance (again in the more historical rather than VW terminology sense) and some (many) repairs boil down to clean, and lubricate, even clearing error codes is a type of electronic cleaning.

Many people, and possibly quite rightly, don't want to know or care about too much detail of why something has gone wrong and just want it working again as that's their priority in their life. When I used to ask my mate why a computer had gone wrong his (wise) short answer was "Because it can!". 😁

Sorry totally my fault about coolant, I'm mixing up your thread with another about air-con (because my brain can, another total brain-fart 🙃) I have far, far too much experience of (old car) coolant system - but thank gawd next to none of German marque cooling systems other than changing the "for life" coolant and the "Simply" brilliant VW coolant numbering system for their unnecessary extra specifications.

IF you can get near at the flap (I'm not sure you can), you may have your own choice but the lubricant, penetrating/releasing agent I recommend for use is GT85 and not WD-40 Multi-Use which isn't as good. (GT85 used to be an English company but taken over by an invasive American corporation, WD-40 company), as Tesco tells us every little helps. GT85 - https://gt85.co.uk/

Again sorry about the coolant refrigerant episode, you're lucky when I threw my hat in the ring it didn't take our eye out, I can't even think of the air-con thread now.

If you want to do more and in depth diagnostics in the future on your car and your son's you might want to check your Autophix, it might be a very good scan tool and great value for money but there's lots of info on the 'Diagnostics & VCDS' forum here and the videos of a good and honest (admits mistakes!) auto-electrician/diagnostics, up your way IIRC(?).

'Diagnostics & VCDS' forum - https://www.briskoda.net/forums/forum/23-diagnostics-amp-vcds/

Milligan Auto Diagnostics - https://www.youtube.com/@mrautoservices7354

I'm off now to find a mirror to see if I can work out the difference between my bottom and olecranon.