[clee1982]

Originally Posted by 530iDriver

Oh you do have a leak, trust me!

Yea but no idea how to get to the "bottom of this" so to speak, take to an independent? What do I tell them to check, run same leak test?

[530iDriver]

Originally Posted by clee1982

Yea but no idea how to get to the "bottom of this" so to speak, take to an independent? What do I tell them to check, run same leak test?

Do you have access to another BMW dealer?

Basically for me it all started like you. Mysterious coolant loss (Twice within a 6 month span). Finally the dealer found the leaking water pump and leak from the coolant turbo line. This was about a year later from the first incident.

Before that diagnostic I was fed the line they all do it, the new turbo engines consume coolant, etc etc.

Have you leveraged and spoken with the shop foreman? Have you opened a case with BMWUSA? You need to start a path of paper trail and escalation as your car is still under warranty.

Your best bet is to get the dealer's service shop foreman involved and open a case with BMWUSA so there is an ongoing paper trail process. This can force them to open a PUMA case. And if they have to fly a factory tech/engineer from Germany, so be it!.

Coolant issues with turbo engines involved are nothing to sneeze at.

[clee1982]

ok, I had low coolant once within first year, so far it hasn't appear again, definitely will go much more aggressive next time if it happen again...

[TourStageFan]

I just picked up a CPO 2018 540iX with 39K miles. I just had the same “Coolant Level Low - top off immediately” warning that others have posted in this thread.
It happened last night, but did not come on again after I restarted the engine.

Should I insist that they perform a leak test as the first step rather than merely have them top-off the coolant?

[Joe-BMW33]

Originally Posted by TourStageFan

I just picked up a CPO 2018 540iX with 39K miles. I just had the same "Coolant Level Low - top off immediately" warning that others have posted in this thread.
It happened last night, but did not come on again after I restarted the engine.

Should I insist that they perform a leak test as the first step rather than merely have them top-off the coolant?

It will come on again soon or next cold restart. Just fib a little bit and tell them you have had to add twice in a month. They will inspect and test.

[TourStageFan]

Originally Posted by Joe-BMW33

It will come on again soon or next cold restart. Just fib a little bit and tell them you have had to add twice in a month. They will inspect and test.

Originally Posted by Joe-BMW33

It will come on again soon or next cold restart. Just fib a little bit and tell them you have had to add twice in a month. They will inspect and test.

Thank you for the advice, it's much appreciated. Our family has a longstanding relationship with our Service Advisor dating back to my father's E39, E60 then my F10 and now G30 so I'm sure he will be helpful.

[Joe-BMW33]

Originally Posted by TourStageFan

Thank you for the advice, it's much appreciated. Our family has a longstanding relationship with our Service Advisor dating back to my father's E39, E60 then my F10 and now G30 so I'm sure he will be helpful.

Excellent, honestly a good SA will exaggerate a little on the write up to get the tech to do what you are asking for. You will get the message again your next cold restart. When the coolant is warm it expands so it goes away when warm unless it's really low.

[bym007]

Just cold started my 2017 540i this morning and got the Coolant low warning. It is cold here in Melbourne Australia. Car has done 88000kms (~50000 miles) and out of warranty now. I bought it used a couple of months back. I turned it off immediately and will inspect the coolant reservoirs shortly.

Doubt if dealers will offer any goodwill for a car out of warranty. Which coolant needs to be bought for topup ? Just preempting my purchase, as it is a Saturday morning and dont want to miss the short window the service center is open.

Edit: Just to add, no signs of leaking on garage floor.

[bym007]

Had had a quick look and noticed that coolant in larger reservoir was well below min level, while smaller reservoir was in between min and max levels. I didnt have any BMW spec coolant at home, so I topped up with demineralised water to the tank.

Service and parts are closed over the weekend, called to find out.

[Bolletta]

Picked up a 12/2019 540i in Germany 3 weeks ago. 20.000 Km from new.
Motor bay looked clean and neat.

After 3.000 Km at high temps, here's what I found:
https://www.dropbox.com/scl/fi/kfptx...3wgsuhqlr&dl=0



No warning about low coolant. Level was just below max. Probably the dealer has topped up over the maximum?

[bym007]

Can anyone please advise, as the G30 has 2 expansion tanks, a larger and a smaller tank, which tank provides cooling for which loop ? My guess is the larger tank is for engine, but could not find this information to confirm.

https://www.realoem.com/bmw/enUS/sho...diagId=17_0988

[EDIT]: Never mind, found this helpful Youtube video.

The larger tank is the only tank with level sensor, so if the iDrive gives the low coolant warning, it is the larger tank needing coolant topup. Secondly, yes I was correct at guessing that the larger expansion tank cools the engine and turbos, so it is pretty critical.

[tsbrown]

My 540i has both main and expansion tanks with level gages. Or maybe you’re referring to the sensor that triggers a warning. The main tank was low so topped it off. The expansion tank was at or slightly below min so added some there as well. Car is coming up 5 years old and has 38k miles. First time getting the warning was about 5k miles and didn’t get again until now.

[Neusser]

Originally Posted by tsbrown

My 540i has both main and expansion tanks with level gages. Or maybe you’re referring to the sensor that triggers a warning. The main tank was low so topped it off. The expansion tank was at or slightly below min so added some there as well. Car is coming up 5 years old and has 38k miles. First time getting the warning was about 5k miles and didn’t get again until now.

Interesting. My car has about 45,000 km/27k miles and I just checked the coolant level today.

No warning on the dash, but main tank below min. mark and secondary tank between max. and min.

In Germany the claim seems to be thermal expansion or a faulty cap.

[bym007]

My car (2017 540i) has thrown low coolant warning twice now in last week alone. Both time, there was no visible coolant leak unedr the car or in the hood. But the main tank was bone dry.

I have topped up with demin water, and it still has colour (cant tell blue or green, without pulling out the coolant). Anyway, taking it back to dealer tomorrow morning for investigation.

[EDIT] Car has 90,000 kms

[bym007]

Originally Posted by bym007

My car (2017 540i) has thrown low coolant warning twice now in last week alone. Both time, there was no visible coolant leak unedr the car or in the hood. But the main tank was bone dry.

I have topped up with demin water, and it still has colour (cant tell blue or green, without pulling out the coolant). Anyway, taking it back to dealer tomorrow morning for investigation.

[EDIT] Car has 90,000 kms

So had my local Indy pressure test the car. Found the main hose to have a leak. Replaced and pressure tested again, looks good. Will keep an eye on the coolant level in coming days.

[Daniels1117]

Originally Posted by nlkccom

This morning the idrive displayed the coolant level low message when I started the car. While topping off the coolant level is no biggie, I was a bit surprised, since I've only had my car for about 4 months, with about 5k miles. Is this common? Happened to any of you?

Just had my low coolant light come on while the engine was off, which I thought was strange. I was cleaning my interior and the gong noise went off. When I started the car the error was gone. Didn’t see the error again for a few days and then the same thing happened, low coolant error when opening car door (engine off). Start the engine and error goes away. After reading many threads on Bimmerpost this seems to be a common issue with the n63tu.

Decided to stop by BMW dealer and pick up some coolant. Just opened the cap today and my coolant was definitely low (under the min level. Added ~500 mL of green coolant + distilled water to bring the level up.

2022 ~32k miles no visible leaks. For what it’s worth I do live in AZ and summer weather is almost over. It is 105-120 degrees F everyday from June-August. Could some of the coolant have evaporated? Car is parked outside often (covered but not garaged) I read somewhere that extreme hot/cold weather can effect coolant levels. Should I be concerned about a leak or is this likely the result of brutal AZ weather.

[HerkHealer]

Originally Posted by Daniels1117

Just had my low coolant light come on while the engine was off, which I thought was strange. I was cleaning my interior and the gong noise went off. When I started the car the error was gone. Didn’t see the error again for a few days and then the same thing happened, low coolant error when opening car door (engine off). Start the engine and error goes away. After reading many threads on Bimmerpost this seems to be a common issue with the n63tu.

Decided to stop by BMW dealer and pick up some coolant. Just opened the cap today and my coolant was definitely low (under the min level. Added ~500 mL of green coolant + distilled water to bring the level up.

2022 ~32k miles no visible leaks. For what it’s worth I do live in AZ and summer weather is almost over. It is 105-120 degrees F everyday from June-August. Could some of the coolant have evaporated? Car is parked outside often (covered but not garaged) I read somewhere that extreme hot/cold weather can effect coolant levels. Should I be concerned about a leak or is this likely the result of brutal AZ weather.

Talk to your SA at your BMW Dealership.
They are programmed to tell you that our V8 engines are designed to burn up and use or lose coolant. It's ridiculous to hear them say it out loud.
It happens to a LOT of M550's and M5's.
The engineers know what's going on, but are protecting it because it must be something expensive to repair.

[Daniels1117]

Originally Posted by HerkHealer

Talk to your SA at your BMW Dealership.
They are programmed to tell you that our V8 engines are designed to burn up and use or lose coolant. It's ridiculous to hear them say it out loud.
It happens to a LOT of M550's and M5's.
The engineers know what's going on, but are protecting it because it must be something expensive to repair.

I’m still under manufacturer warranty for about 1.5 years or so. I’m not super concerned but I was surprised to see so many threads related to this “issue”.

[Neusser]

I sometimes wonder what effect the engine cover has on these leaking coolant lines. With the foam insulation on the hood, the active grill and the underbody paneling, the heat is trapped enough as it is. Is the cover and its foam liner contributing to this problem?

I've been running without it for about 10,000 kms, and have no plans to put it back on. Plastic and heat do not mix.

[Joe-BMW33]

Originally Posted by Daniels1117

I’m still under manufacturer warranty for about 1.5 years or so. I’m not super concerned but I was surprised to see so many threads related to this “issue”.

It’s probably the only issue with the car to speak of when someone asks what should I look out for. Could be worse. It’s permanent fixable or long term at least.

Coolant message is supposed to pop up when you turn off the car. Completely normal.

[Chappers 71]

In my years of BMW ownership all of my cars have had to have coolant added occasionally & from my own experience & research it’s normal for an engine to use a little coolant.
For example I added 200ml (0.21 US Quarts) to the engine coolant tank this morning & 75ml (0.08 US Quarts) to the intercooler tank. Car had been serviced by supplying dealer when I bought it 14 months ago first thing I did was check all fluid levels when I got it home & coolant levels were all at max, I usually check levels once or twice a year & top off as required.

Obviously if you’re having to add a lot more coolant & often then there’s an issue but adding up to 500ml (0.52 US Quarts a year I reckon is normal

[ezaircon4jc]

Originally Posted by Chappers 71

In my years of BMW ownership all of my cars have had to have coolant added occasionally & from my own experience & research it’s normal for an engine to use a little coolant.
For example I added 200ml (0.21 US Quarts) to the engine coolant tank this morning & 75ml (0.08 US Quarts) to the intercooler tank. Car had been serviced by supplying dealer when I bought it 14 months ago first thing I did was check all fluid levels when I got it home & coolant levels were all at max, I usually check levels once or twice a year & top off as required.

Obviously if you’re having to add a lot more coolant & often then there’s an issue but adding up to 500ml (0.52 US Quarts a year I reckon is normal

I never understood that as the cooling system is a sealed system. The only way to "use" coolant is due to a leak somewhere in the system.