By YOUCANIC on Dec 19, 2018
Is your BMW Low Coolant Level Warning on? Checking the coolant level on a BMW is easy and takes less than five minutes. It is crucial to follow the correct procedure to avoid injuries and get an accurate reading.
Ideally, you should use Genuine BMW Coolant or an acceptable BMW coolant alternative. Before you can safely check BMW coolant level, you need to wait for the engine to cool down. Here you will find instructions to check the engine coolant level and add coolant to any BMW.
Older BMWs had a translucent coolant reservoir with a line that shows the high and low level. Back then it wasn't necessary to remove the cap to get a coolant reading. BMW redesigned the cooling system, and now they use an expansion tank. Instead of the transparent tank, they implementing the float design ( the rod that pops up).
Follow these easy steps to check the coolant level on any BMW. Make sure engine is cooled down before you remove the cap from your coolant reservoir or you risk getting burned. There are no special tools needed to top off BMW cooling system.
Always check BMW coolant level when the engine is cold. Not only due to safety reasons, but also so that you get an accurate reading.
Park your BMW on a level surface. Engage the parking brakes and move the shifter in Park. Allow your BMW engine to cool down. At least 30 minutes. Preferably more. If you decide to open the cooling system right after you turn off the engine, you need to be extremely cautious to avoid getting burned.
Once your BMW engine has cooled down, open the hood. Pull the hood release under the dash.
As you open the hood, look at the left of the engine bay. This is the typical coolant expansion reservoir location. Some BMW models such as 3-series have the coolant expansion reservoir on the right side of the engine bay.
Turing it slowly will allow residual pressure to release without blowing off the cap.
There are two different float designs.
If the float is all the way down you need to add coolant. If the float is sticking up your BMW coolant level is full. In other words, BMW coolant level is correct if the red float is aligned with the top edge of the filler opening. There is a schematic diagram stamped on top of the coolant reservoir illustrating the min and max level. Rember the level reading should be performed on a cooled down the engine for proper measurement.
If you see any seepage or coolant leakage around the cap you may keep getting the low coolant level. The cap may not be holding the pressure and could be leaking coolant. Replace the cap. Also, clean the cap as there can be a buildup of solids not allowing the rubber to seal the system and cause a leak.
Typically to top off the system you don't need to add more than one quart/litter. To make the float move from the minimum level to maxim you need less than a quart of coolant. If you have to add more than one quart, you may have a coolant leak. If you are constantly adding coolant to your BMW or have to add more than one gallon of antifreeze, you may have a major coolant leak or a serious engine problem such as a blown head gasket.
BMW uses a closed pressurized coolant system with an expansion tank. It operates differently than most coolant systems which have an overflow reservoir.
What you will need
By allowing the BMW to idle and setting the heat on it allows the air pockets in the cooling system to escape. If you suspect air pocket in the engine and used this method, recheck the coolant level with the engine off. This will ensure you didn't overfill the system.
If your BMW is under warranty, take your car to the dealer and they will top off the cooling system free of charge.
Not all aftermarket coolant are compatible with BMW cars. BMW recommends that you use their approved coolant. If that is not available there are a few coolant/antifreeze brands that are compatible with BMW cars.
Regardless of the coolant brand you use including OEM BMW Coolant, always pre-mix it at 50% coolant and 50% water. Full strength coolant is not mixed and you will need to mix it yourself before adding it to the cooling system. Use distilled water instead of tap water. Tap water will work, but it is not recommended because it can introduce impurities, minerals and also cause corrosion to the cooling system over time.
You do not need any extra additives. The 50/50 mixture ratio can be used year round.
It is possible to still get a Coolant Level too Low warning even if you add coolant. The first thing that you need to inspect is the coolant level sensor if your BMW has one. It is possible that there may be an electrical issue with the sensor causing it to trigger the warning message.
If you are extremely low in coolant, you may get the low coolant warning light even if you add coolant. The car was either neglected or was extremely low in coolant. Run the car for one minute and recheck the coolant level. It is possible that you need to add more coolant.
Is BMW coolant warning message on, even though the coolant level is correct? This may be caused by outside temperature fluctuations or when using certain incompatible aftermarket coolant brands. Other possibilities include defective water pump, bad engine temperature sensor or bad coolant level sensor.
Coolant and oil are two of the most critical fluid in your BMW. Driving without those can cause serious engine problems. The issue with coolant system is that even if the coolant level is full, it may throw the warning message due to a defective sensor. Despite everything else still working correctly.
If that is the case, monitor the temperature gauge. If your BMW has not been overheating or running too hot, it may be ok to drive the car. If the temperature gets above normal or you get a warning light that engine is overheating, stop driving your BMW. Get it towed to a mechanic ASAP.
It is possible that the coolant level is extremely low causing the float to be much lower than the min. In this case, it may be hard to see the float. Use a flashlight to look inside the coolant reservoir.
If the float device is not present it may been removed or broken.
No. Low coolant level warning should not turn on service engine soon or check engine light. Unless the coolant system is almost empty in which case the engine temperature sensor may malfunction triggering the check engine light.
If you overfill the cooling system, it may cause it to be overpressurized. Excessive coolant will be released via the release valve on the cap.
Most BMW cars, including 1-series, 3-series, 5-series, X1, X3, X5 use blue coolant.
Yes, but its not recommended. With that said, it is better to have some coolant than driving a BMW with no coolant at all. Once you get your car to a mechanic, you may want to do a full system flush and install the correct BMW coolant.
If BMW coolant too low warning light comes on and then turns off the level may have dropped slightly. Check coolant level and add as necessary.
Any BMW owner looking for help with the following topics:
When you have a BMW coolant leak you will notice a distinct sweet smell that wasn't there before. You may smell coolant in the cabin. Or you may smell the coolant leak when the car is parked. After driving the BMW for a few minutes, open the hood and inspect for coolant leak.