It could be your matrix. Hard to be sure. What did you fit when you say non-genuine?
Some people have had other contributory factors such as issues with EGR cooler or pump I think.
Or stick in another matrix and see how you go.
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No heat from vents
- Thread starter Telscossie
- Start date
Some people have had other contributory factors such as issues with EGR cooler or pump I think.
Or stick in another matrix and see how you go.
I just left the car at an authorised Seat service with a similar issue. They searched one full day and they told me to leave the car there for even more investigations as the water pump was recently changed, the heater matrix was not blocked and no error was shown on the tester. Although it’s not the same model, it might be useful for you as well:
They called me and told me there is a “solenoid” that was stuck in closed position which caused the whole issue. They quoted around 150€ for the part and a bit more than that for all the work. Hope this helps.
They called me and told me there is a “solenoid” that was stuck in closed position which caused the whole issue. They quoted around 150€ for the part and a bit more than that for all the work. Hope this helps.
What engine do you have?
Most of the 'heater matrix problems' here are relating to the TDI. Assume you also have a TDI?
When my matrix blocked up (several times as at first I tried back flushing the matrix - which was only ever a temporary fix) it was never 'intermittent' i.e. one day bad/cold - next day good/hot - when it stopped working it stopped working! It was also only ever the drivers side/RH - passenger side was hot.
As the internal micro tubes of the heater matrix slowly block up with silica/detritus/junk/casting sand/corrosion etc.. it restricts flow through that part of the matrix - which usually happens to be the part of the matrix which provides heat for the RH side of the cabin.
The genuine one may actually be worse for blocking up - just my hypothesis - they are using very small bore tubes to get quick heat transfer - BUT at the expense of easily blocking up. A good aftermarket version may use slightly larger bore tubes?
I replaced mine with a none genuine heater matrix - but good quality aftermarket (NRF 54342) and its been fine since. I don't think your problem is genuine vs aftermarket heater matrix.
More likely trapped air - if its an intermittent problem?
Feel the pipes from the matrix - what temperature are they - one will get hot first, this is the flow, the other pipe, the return will get hot slower. Should be slightly cooler than the flow if the heater matrix is working properly taking some heat out of the coolant and your heater demand is high.
This cooling system is very complicated - with 4x circuits, one way valves and 3x pumps.
Presume you replaced the heater matrix after you flushed the cooling system and not before?
Which engine does your car have, it sounds like it is a Petrol engine, but which version?
Ah, so Cupra, my older daughter has one of them, a 2019 car. I have been trying to get her to consider funding me to replace her coolant reservoir which is a "mit silikat" one for one that has no silicate pouch in it, maybe I'm being over cautious but better to change that and move across to G12evo next spring from the G13 that requires these silicate salts adding in.
Hi all,
I have a 2016 SEAT Leon with the same issue. What I'm trying to determine is whether it's expected or actually an issue, before I take it to a dealer.
This is a particular problem now because of the weather, with it being -2 to -4 a lot of the time, and also humid, the inside windows are always coated in condensation and/or ice.
I switch the engine on and have the heaters on full and heat turned to max blowing on the windscreen, but it does nothing. I can leave it for 10 minutes and it'll be no different - the air coming out is ice cold. I actually need to drive the car and get up to 40mph for 10-15 minutes before it's capable of blowing hot air out the vents.
It seems weird to me because my previous (older crappier) car was able to produce heat from the air vents quickly, in fact it was the main way to defrost the car in the morning. Whereas I have to drive this car wearing a thick coat and gloves and poor visibility, because I cannot get it to warm up on the driveway, the only way for it to produce warm air is to drive it for 10-15 mins.
I do notice that there is a dial under the throttle display which I think is the oil temperature, which is on one bar until I have been driving for about 15 minutes, and then it goes to the halfway point which is where it should be, and the car is only capable of blowing warm air after that. Is that normal?
I have a 2016 SEAT Leon with the same issue. What I'm trying to determine is whether it's expected or actually an issue, before I take it to a dealer.
This is a particular problem now because of the weather, with it being -2 to -4 a lot of the time, and also humid, the inside windows are always coated in condensation and/or ice.
I switch the engine on and have the heaters on full and heat turned to max blowing on the windscreen, but it does nothing. I can leave it for 10 minutes and it'll be no different - the air coming out is ice cold. I actually need to drive the car and get up to 40mph for 10-15 minutes before it's capable of blowing hot air out the vents.
It seems weird to me because my previous (older crappier) car was able to produce heat from the air vents quickly, in fact it was the main way to defrost the car in the morning. Whereas I have to drive this car wearing a thick coat and gloves and poor visibility, because I cannot get it to warm up on the driveway, the only way for it to produce warm air is to drive it for 10-15 mins.
I do notice that there is a dial under the throttle display which I think is the oil temperature, which is on one bar until I have been driving for about 15 minutes, and then it goes to the halfway point which is where it should be, and the car is only capable of blowing warm air after that. Is that normal?
With any car built over the past 20 years, I'd never plan or expect it to generate enough heat warming it up on the driveway - which in itself is a very antisocial thing to do.
If you are finding a lot of condensation building up in your car overnight, then find out why it is doing that.
For instance, EA211 family of petrol engines only seem to produce as much waste heat as a TDI engine.
I tend to garage our cars, and I only switch the "heating" on for short bursts to keep the windscreen clear, until the engine is up to normal working temperature as stripping waste heat out of a cold engine will slow down it keeping up to normal operating temperatures - as indicated by the coolant temperature. If your own car does not have an engine coolant gauge, then shame on SEAT for that.
Edit:- @Debaser, which engine is in your Leon?
If you are finding a lot of condensation building up in your car overnight, then find out why it is doing that.
For instance, EA211 family of petrol engines only seem to produce as much waste heat as a TDI engine.
I tend to garage our cars, and I only switch the "heating" on for short bursts to keep the windscreen clear, until the engine is up to normal working temperature as stripping waste heat out of a cold engine will slow down it keeping up to normal operating temperatures - as indicated by the coolant temperature. If your own car does not have an engine coolant gauge, then shame on SEAT for that.
Edit:- @Debaser, which engine is in your Leon?
Which engine?
My Leon TDI 184 blows warm air out the vents within a 1 - 2 miles.
I also have an electric heater but this only kicks in when cold out and certain criteria are met - like when you are driving/ not sat idling, but to be honest it gets warm so quick I don't think the electric auxiliary heater kicks in much.
The TDI has a micro heating circuit to enable quick heat up of cabin air and EGR valve.
Should be able to blow hot air once the engine is warm. Sounds like either your coolant system isn't getting hot and/or your heater matrix is blocked.
Do you get hot air out the passenger vents - vs warm/cool driver vents?
I have a similar problem in my 1.9TDI MK2 Leon. Car heats up to a steady 90/91C & blows hot air. After around 10 minutes the heater starts to blow cold air However, the engine isn't overheating. BTW where is the matrix? Does it require dismantling half the dash (or being a contortionist) to get to it?
That's bad. I watched a video a mobile mechanic put up on Youtube a while ago. The case was an Audi estate with an electric tailgate that stopped working.
Apparently the Audi stealer wanted £1000 to fix the fault which turned out to be a switch (sensor?) which fits just above the lock. The mechanic obtained the part for £5. And the only labour involved was removing the trim, fitting the part and replacing the trim again.
I wonder how many years will pass before dealers will be expecting £100's just to replace a fuse?
Sorry for going off topic
Hi all. I recently had a timing belt kit done by a local garage including waterpump. I only realised a couple of months later that I get hot air on passenger side but not the driver side and AC seems very weak not blowing very cold air or hot. Any ideas?
Based on the lop-sided heat alone, I would guarantee you need a new heater matrix. These clog over time, and something like a complete drain down, re-fill and bleeding of the main cooling system will dislodge a load of extra sludge - and guess where it ends up! The AC system fault is beyond me - possibly a pre-existing fault that has come to light now? Others will know better, but if you check your coolant bottle after a decent run, there will be tell-tale fluid around the cap, because the heater circuit (separate from the main and regen circuits) will have over-pressurised and blown off. My first encounter with this issue happened in the summer months, and it was the coolant level warning light that alerted me.
There are loads of resources on the matrix, I am now on my 3rd one (10 yr old Mk3 with 200K+ miles!) and have replaced them all myself and can now do the job in under an hour. You don't need to take the dash out, just remove the glove box and be prepared to catch the small quantity of coolant that comes out when you disconnect the existing pipework. I use a small water bottle with the bottom cut out to catch the coolant, with some polythene sheet and old towel as a back up. My tip would be to use a couple of 3" g-clamps to clamp off the flow and return pipes as they pass through the bulkhead in the engine bay, into the cabin. Its a total b@st@rd to reach, but worth it, I think. Once the job is done there will be air in the system and this approach does reduce it a bit. Apparently there is a bleeding protocol available via the OBD - I just went old school and run the car up to temp, and carefully opened the cap to let air out, and then topped up as required. Takes 2 or 3 cycles. Here are some links which will help:
https://www.seatcupra.net/forums/threads/how-to-remove-the-glovebox-media-unit.457061/ The only tool I had to buy was long-reach/flexi drive to reach the back torx screws on the fan cover (see video below).
https://www.autodoc.co.uk/nissens/7589648#heater-matrix (Check the part number for your model)
If you're at all handy (I'm not) this will be breeze. Good luck.
Thanks for the information. Am Not handy but a little lol. Not worked on cars for a few years when engine bays etc got too small to work in lol. Will have a look. I am going to speak to garage who did the water pump see if they forgot to connect something or maybe willing to do pressure check after I do the work. Modern cars always something to be doing. My other car 34yrs never has issues.
Good luck - the flow and return connections are fully visible on the matrix with just the trim panel removed from the transmission tunnel.(See my profile picture for evidence!) So, you can put everything back together (except the trim) and run the engine up to temp to check your connections are not weeping. This will save paying the garage. It is pretty easy to not quite get the lower connection perfectly seated (I've done it once out of 3) as demonstrated in the video. But easily corrected.
For a weak AC - normally that would be low refrigerant - so you'd need a re-gas if you haven't had one in a few years.
For uneven heating that could be a partially blocked heater matrix as mentioned previously. Quite simply to change DIY.
Assuming you have the auto AC - Might also be good to do a flap recalibration - its good practice to 'cycle your flaps' regularly to keep them working well, to hot to cold and screen to face to feet a few times once ever month or two, you don't want to get a seized flap servo motor/link!
I did look at this video but my controls are different to the ones shown in the video no buttons just dials only. According to the car the AC levels are fine showing three blocks.
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