[MCL_24]

I got in my 2019 540xi this morning and before even starting the engine the onboard screen alerted me that the engine coolant needed to be topped off.

I needed to drop my kid off at daycare (5mi away on local roads) so I decided to drive easily there and then figure out what to do when I got home.

When I started the car to leave daycare, interestingly I didn’t get the notification… making me wonder if it was a bit of a fluke.

Anyway I’m assuming I should get some coolant asap and look to top it off.

My question is…. will my dealer sell me a gallon at a reasonable price? I could order from FCP Euro or a site like that but won’t receive it for about a week…

Or would be be ok to go to an auto zone and get the European formula coolant that they claim is fine for my car? (Assuming this won’t be a popular vote on this forum lol)

[Chappers 71]

You won’t need a gallon, you can get a 1.5litre top up, I always keep a bottle of bmw coolant handy.

[RonronEG]

I'm in California- BMW dealerships I've been to top up coolant at no charge. I first got a coolant message on my way home from work and rolled into the closest dealership and they filled it. Happened a second time, same result. I did end up buying my own coolant and carried some in a 20oz bottle for top ups on my own.

[Joe-BMW33]

Only use BMW approved/branded coolant. Do not use auto part store coolant. You probably have a small leak, so it might be a good idea to order some concentrate from FCP. I mix with distilled water.

The dealer will definitely top it off for free, but that is a hassle. Also, in general, you will get the low coolant warning the minute you shut off the car, it will come back. You are probably right on the edge of low and ok.

[Qsilver7]

Since the cooling system is pressurized...if the engine is cool...and you get a low warning...once your start driving around and the engine comes up to operating temps...the coolant has expanded...thus an initial low coolant warning on the cold engine can go away. But if the system is low..when the engine cools off...the warning will come back.

Because of this "expansion"...I recommend topping off when the engine is cool (if possible). But if your local dealer will top off for free...who can argue with that.

Your BMW uses an HT12 coolant (its green, now...not blue). You can pick up some BMW branded coolant from your local BMW dealership's parts department. They may have straight and/or pre-mixed...you can ask them.

If you go aftermarket...look for the old blue g48 or the new green HT12...they are compatible and can be mixed...but not sure what color you would end up with.

As mentioned above...the dealership's parts department sells a 1.5L bottle (#8 in diagram below) as well as a larger 1000ml jug.

[AP]

Just search this forum and you will see that this unfortunately a common issue
I’ve had it myself and it was one of the reservoirs (yes there are 2)
Very small leak which was only apparent with a torch shining down into the engine apartment where there was a small amount of residue
As others stated you get the alert when cold but it will go away when warmed up until of course it drops below that threshold

Don’t be fobbed off with dealer stating this is normal as it is not and the system should not leak

[Chappers 71]

Originally Posted by Qsilver7

Since the cooling system is pressurized...if the engine is cool...and you get a low warning...once your start driving around and the engine comes up to operating temps...the coolant has expanded...thus an initial low coolant warning on the cold engine can go away. But if the system is low..when the engine cools off...the warning will come back.

Because of this "expansion"...I recommend topping off when the engine is cool (if possible). But if your local dealer will top off for free...who can argue with that.

Your BMW uses an HT12 coolant (its green, now...not blue). You can pick up some BMW branded coolant from your local BMW dealership's parts department. They may have straight and/or pre-mixed...you can ask them.

If you go aftermarket...look for the old blue g48 or the new green HT12...they are compatible and can be mixed...but not sure what color you would end up with.

As mentioned above...the dealership's parts department sells a 1.5L bottle (#8 in diagram below) as well as a larger 1000ml jug.

This post had me a little concerned as my local md sold be blue top coolant of which I added 150ml to the engine tank & around 50ml to the intercooler tank (diluted 50/50).
So I gave them a call & it turns out that cars with a build date of before June 2018 use the blue coolant NOT HT12

[Qsilver7]

Originally Posted by Chappers 71

This post had me a little concerned as my local md sold be blue top coolant of which I added 150ml to the engine tank & around 50ml to the intercooler tank (diluted 50/50).
So I gave them a call & it turns out that cars with a build date of before June 2018 use the blue coolant NOT HT12

Not sure for the concern…the date ht12 started to be used is highlighted. I had no clue of your 2018 build date…so i posted enough info to check which chart your model falls under. But it still doesn’t matter because the blue g48 & green ht12 are compatible…so either can be used and/or mixed.



And the 2nd chart at the bottom also lists the models & the dates that the old blue g38 was used.

[530iDriver]

These cars are notorious for cooling system problems.

I have gone through 2 leaky water pumps, and 2 instances of melted plastic cooling return lines that have resulted in zero coolant in the car.

These issues are caused by poor quality plastics used in the end fittings of the coolant return lines. This is one reason why I hesitate to go to BMW for my next car.

Don’t allow the dealer to convince you or talked you into believing it is normal to have to top off coolant or abnormally high coolant consumption. “They all do it” is a LIE don’t ever believe it for a second!

BMW’s use of cheap melting plastic components on mission critical systems under the hood like cooling, reeks of bad faith and total disregard for the paying customer. Would not be surprised if there is a class action suit in the making.

Also their top tier BMW Platinum extended warranty does not cover their prone to failure and defective coolant return lines. Hmmmm, I wonder why😆

[bigscore]

I just went thru this last week.

The culprit was a leak in the radiator on the top drivers side.

[Neusser]

Originally Posted by 530iDriver

These cars are notorious for cooling system problems.

I have gone through 2 leaky water pumps, and 2 instances of melted plastic cooling return lines that have resulted in zero coolant in the car.

These issues are caused by poor quality plastics used in the end fittings of the coolant return lines. This is one reason why I hesitate to go to BMW for my next car.

Don’t allow the dealer to convince you or talked you into believing it is normal to have to top off coolant or abnormally high coolant consumption. “They all do it” is a LIE don’t ever believe it for a second!

BMW’s use of cheap melting plastic components on mission critical systems under the hood like cooling, reeks of bad faith and total disregard for the paying customer. Would not be surprised if there is a class action suit in the making.

Also their top tier BMW Platinum extended warranty does not cover their prone to failure and defective coolant return lines. Hmmmm, I wonder why��

Audi has the same problem.

I run my 540 with no engine cover, as I believe it contributes to the heat issue that destroys the plastics. I also suspect the active grill plays a role.