Thanks for accept me.Just bought a Skoda Superb Estate iV Hybrid from 2020 and after few days I receive this error mesage "cooling system" ,and when I take a look, the right side tank was empty (tank for cooling electronics).After I get out the pipe slowly, I flush a lot of air and the coolant was back on the normal level !!! Its happend all the time after I drive more on electric, I must to stop, flush again and all good for a while.Pls help me with some ideea.Thank you.

Please describe what you mean by flush the system and flush air?

I take out the rubber hose slowly and I let the air to go out.

Because the cap was sealed.

You need to visit a Skoda or even VW/Audi dealer for specialist help. I doubt anyone here can help. As the coolant reservoir is sealed, I don't think its wise to start removing pipes. Especially as its a cooling system for the electronics and battery and the warning label makes it clear you shouldn't mess about with it only qualified technicians.

Those warnings would be too much for the curious child in me!

 

To the OP, you should only release the cap or the pipe when the system is stone cold, you have a low fluid level which the system has detected, doing what you did just releases the compressed air allowing the heated coolant to expand into the space, if done cold you could top up.

 

I would not take it to a garage but thats me and I'm not advising others what to do, I would cut through the tamper seal as the garage would and remove the cap not the hose to top up.

 

They will be doing the same thing with windscreen wash fluid next, more fool anyone buying a new car

Edited 5 March, 20242 yr by J.R.

There is a clear warning not to top it up. I don't understand why, but as this is a safety related system, cooling the main Li Ion battery, I wouldn't mess with it until I had detailed knowledge about this particular system and its servicing requirement. You would certainly need to know exactly what coolant, concentration, level and whether the sytem is permanently pressurised.

 

There is likely a leak somewhere, which might be a safety issue.

 

See the dealer and ask them for advice.

24 minutes ago, J.R. said:

Those warnings would be too much for the curious child in me!

 

Curiosity killed the cat

Yeah, I've paid the price a few times but like a cat seem to have 9 lives.

Dob't see any leak, after the engine is cold, the coolant is back to max level.Today I drive it few hours in the city and nothing!!! This seems to happend after I don't use the car for a week.Thank you all of you for answers.

There have been posts in the Octavia MK4 section about iV,s / PHEV,s and a coolant TPI.  Maybe on here as well.  Have the issue logged for the sake of the warranty.  Check if there is a a Skoda Recall Action or any information only given to those that talk with them. 

7 hours ago, J.R. said:

Those warnings would be too much for the curious child in me!

 

7 hours ago, xman said:

There is a clear warning not to top it up. I don't understand why, but as this is a safety related system, cooling the main Li Ion battery

 

The reason this coolant system is sealed is like you said - it cools the HV battery and HV components - if this level drops then there is a good chance of there being a leak - this means external and risks frying HV components or internal and risk starting a lithium fire or HV charging the vehicle chassis (Although extremely unlikely considering the safety involved in a HV battery). Its sealed for this very reason and if the level drops and your average joe just keeps topping it up, then problems are to be expected.

 

That and from a warranty point of view there is a clear indicator the cap hasnt been opened so no incorrect fluids have been added.

 

If I had my way this should be done with the brake fluid cap as well. All to often when i worked in retail years ago people would come in just needing a 'brake fluid topup' and whereas my alarm bells are ringing about possible leaks and low pads, the customer and other colleagues just see it as low means top it up and forget about it.... (And you can be damn sure they 'knew exactly what they were doing' and wouldnt take any advice from me.)

Milet. Did you find out what the problem was as mine has just started doing the same?

Hi, no mate, I just filled with disteled water, and suddenly is stopped!!! Very strange ! Big enigma ! Now its ok!

Has only happened once so maybe might be a one off and not do it again but thanks for letting me know. Will just keep an eye on it

On my car qas happend when I drive only in weekend , after I take it  the taxi plate and deive daily about 150miles, is back to normal!.When ws happend, I open slowly the cap with a towel  covered to not spil liquid, and I refil, be careful, its dangerouse.Good luck !

Happened again. Took it into dealer and has had the heat exchanger on the high voltage side changed. Good job its still under warrenty.

Can you explain with more details please? And the cost ? Thank you.

Not too sure on details but from what I understand the battery invertor uses a heat exchanger that is also connected to the air con. On mine there was a leak between the 2 sides and the coolant and ac refrigerant we mixing and leaking. They have replaced the heat exchanger now so hopefully thats fixed it. As far as price goes I dont know as was done under warrenty but did have a quick look at the part and was around £900 if that was the right part.

@Milet Is your car used as a Taxi?

Best get the diagnosis carried out and the repair done as you have a responsibility for the safety of customers.

Thank you!

Had exactly the same issue on my Superb IV this weekend. Called Skoda assist this morning who sent out one of their own VAG techs. Too bloke, ex Skoda master tech so knew his onions..Said it was a well known issue with a technical service bulletin. He removed the security seal and the header tank filled back up. Followed me to my local dealer where it now awaits a new part for the air con system which is over pressurizing. 

Good luck, pls update when is done! Thank you.

Car now returned with the offending part replaced under warranty. The service guy commented they'd dealt with a few IV's and VW GTE's with the same issue, and a technical service bulletin is in place.

Thank you for your info!