What does it look like: A thermometer with wavy lines
What color is it: Red
What does it mean: The low coolant light illuminates when your BMW’s engine is too hot. This is detected by your BMW’s computer, which monitors the coolant temperature and fluid level to make sure it is always at the proper temperature.
What to do when it comes on: Upon engine start-up, you’ll see it illuminate and then turn off. If this light does not turn off, it indicates that there is an issue—either the coolant level is too low or there is a malfunction within the coolant level sensor system. In some models, you’ll see a message appear in your instrument cluster.
When the low coolant light is illuminated, and you are driving, pull off the road safely (if you are not already parked, upon engine start-up) and turn the engine off to let it cool down for at least 30 minutes. It is risky to keep driving when this light is illuminated, as you may cause significant damage to the BMW engine. After waiting at least 30 minutes, pop the hood and check the coolant fluid level. Note: Do not remove the radiator cap until the engine is completely cooled down.
What steps need to be taken to turn light off: If the coolant level is low after checking, you may add a little bit of water so you can drive to your neighborhood BMW service center to get it professionally examined. You can also add the proper amount and type of coolant if you have it handy, but it is also wise to bring it in to your nearest BMW mechanic for inspection. If the problem isn’t solved, it is likely to persist and you risk damaging your BMW’s engine.
Usually, a low coolant level means there is a leak, and your expert BMW repair shop will check to see if this is the case or if the engine is consuming large amounts of coolant, or if there is a malfunction within the warning system.