[frankchn]

It is the blue coolant -- my dealer's parts department verified it. The yellow-green color you are seeing is the level indicator (which is yellow) in the blue coolant, which appears green when mixed.

[Shaq in the Ozarks]

Had this happen this fallin my 2017 M550 with 10 K miles
Brought to the dealer as it did the same ting
Car left at airport and we had a cold snap with temps below freezing
Turn on car warning came on for 30 mins drive home Next day off then on after 15 min commute to wok
Brought to dealership
Bad news
Intercooler radiator seal failed
4000 repair under warranty car out 2 weeks
apparently the Hot V set up for the twin turbos gets quite hot
Saw an opportunity to get into a M5C
Goodbye M 550 pass on Panamera GTS /Taycan
Hello Darling M5C with performance exhaust
Apparently the M cars do not have intercooler issues as of yet I was told by service manager
We will see
Moral of story Have the coolant issue checked out

[Murphy33]

It also happened to me in cold weather. In winter, the liquid is shrinking in volume, so everybody sees it after a cold night like me when I was in the mountains. After driving a few kilometers down at the gas station and restarting the signal disappeared. However, I checked both coolant tanks and were below the minimum.
So I did some research on coolant. It's very hard to find what coolant BMW is using, but I found out. It is:
- C11 / G11 concentrate, which must be diluted 1: 1 with water
- G48 is already diluted and is therefore better for use. Usually it will be enough to buy 1 liter to refill.
I hope I helped someone.

[Azuriteleb]

Regarding the "low coolant warning" issue, It fairly looks like what I am experiencing now for the third time. First time @4000km second time @8000km and third time @13000km on a brand new M5 MY2019. At the dealer they did the pressure test. Result: nothing abnormal; They did bleeding procedure and refill @8000km but it happened after @13000 km. The system being a closed circuit, any evaporation is expected to stay within the system. It would be interesting to know by how much you had to top up until you reached the required level. They say around .5 liter to 1 liter. More importantly, it would be interesting to know why this alerts comes on and then goes off between different engine starts and without leaving any traces on the faults log that you can see on the vehicle status dashboard before coming on again after few trips. I expect a recall for the expansion tank to be notified soon. They call it now technical campaign. Did anyone experience this? Are you aware of any active recall to fix?

[kdeleon]

I brought in my car for an oil change and mentioned the low coolant. They performed the pressure test as it was recommended for my service. Everything tested out fine. The dealer said it was perfectly normal for turbo charged engines to burn off some coolant.

I have also had to top things off once a year.

[callcouchpotato]

Had the same message at the weekend but coolant was topped up by the technician with 1 litre of coolant in the larger tank but none required for the smaller tank after 13k miles with no oil warnings.

However, for the F10 M5 no coolant was needed having completed 20k miles but needed oil every 800 miles....

Go figure?

[MA///M5]

what the f do I have to do to the cover off?

[MA///M5]

sorry, not the cover, the cap?

[Used2be]

Originally Posted by MA///M5

what the f do I have to do to the cover off?

It's a bitch, isn't it? I think the heat makes the coolant some sort of adhesive for the plastic cap! I had a hell of time the first time I took it off, but cleaned the cap and sprayed some silicone on the threads. It's been fine since. I used two hands to turn the darn thing, just have faith.

[MA///M5]

Originally Posted by Used2be

It's a bitch, isn't it? I think the heat makes the coolant some sort of adhesive for the plastic cap! I had a hell of time the first time I took it off, but cleaned the cap and sprayed some silicone on the threads. It's been fine since. I used two hands to turn the darn thing, just have faith.

thanks! Did you go all the way around counterclockwise, or was it in the "feel loose" stage before turning that far?

[Used2be]

Originally Posted by MA///M5

thanks! Did you go all the way around counterclockwise, or was it in the "feel loose" stage before turning that far?

As I remember it was pretty tight until not long before it was completely unthreaded. A couple of complete turns maybe. You're not screwing anything up if you keep turning, there's nothing that can break.

[MechEng90]

Random question, does anyone know what the coolant temperature is within the engine? can't seem to find this number with any of the coolants used on the F90

[shellbmb]

Got the low coolant warning and assumed it was because of the sudden cold weather. Anyways, thought I'd top it off anyways and just pinged my SA asking if the Zerex G48 was correct and he said probably, but just make sure the coolant in the reservoir is blue.

So I drew up the coolant in both reservoirs and they were not blue, and not the same. Main engine was orange and secondary was green.

I'll take it in and get it topped off, but just thought that was strange. Guess I can put in distilled water in a pinch.

Blue was the Zerex G48 bottle.

Why would they use two different types?

[shellbmb]

Answered my own question. My SA talked to the shop foreman and they said the cars come from BMW like this with two different colored coolants so they can identify leaks better. Makes sense.

He also said fine to mix the blue coolant with either if needed to top off.

Learn something new every day.

[RichF90M5C]

Had the coolant light came on, in my car a couple of times last week, so topped it off, it hasn’t come on since. Car has done 7k miles. First time I’ve had to do that on any car, so I was surprised.

[pmsteinm]

When it got cold the first time in October mine was low (.5l to get to min). The coolant level changes quite a lot based on temperature. I think you need it in the middle of min/max when it's 65 out...at max when it's 100 and at min when is in the 20s.

I'm keeping an eye on mine. The dealer over filled when they tested but that seems to have possibly fixed my possible cap leak (I guess the coolant blowing by the cap lubricated the o-rings or something). Now I have no white spots under the hood (after a massive cleanup effort after the overfill).

[Terrier15]

I’ve had the low coolant warning maybe a half dozen times on my 2019 comp. I just stop by whatever BMW dealer I’m near and they fill it in five minutes and, of course, don’t charge. My dealer’s service manager tells me this is very common, because the gauge to trigger the warning on the current M5’s is like a couple millimeters, so “low” isn’t an urgent situation.

[Alberta]

Originally Posted by Terrier15

I’ve had the low coolant warning maybe a half dozen times on my 2019 comp. I just stop by whatever BMW dealer I’m near and they fill it in five minutes and, of course, don’t charge. My dealer’s service manager tells me this is very common, because the gauge to trigger the warning on the current M5’s is like a couple millimeters, so “low” isn’t an urgent situation.

It is not a common issue.

I've only had the warning once since I own the car and driven it about 43k miles.

[Maverik259]

Originally Posted by Alberta

It is not a common issue.

I've only had the warning once since I own the car and driven it about 43k miles.

never had a single coolant light on my 2020. sitting @ ~25k miles.

[Autoregression]

55k on a 2020. I've had a single low coolant warning.

After verifying the coolant tank was not leaking, I added about a quart to top off the system.

[pbonsalb]

I have never had a low coolant warning but check the tank periodically. Some say the warning is triggered if the level drops just a few mm, you say you needed to add a quart when the warning triggered, and some say their tank failed and damaged injectors with no prior warning light. I am not sure what to make of the inconsistent warning light except to not rely on it.

[ResIpsaLoquitur]

‘19 and ‘22 F90, combined service of 45k miles. No less than a dozen low coolant warnings between both, though I’ve never had the expansion tank or cap fail.