Mercedes Coolant Warning Light – What should I do?

The Mercedes coolant warning light displayed on the Mercedes dashboard notifies that the engine coolant level is low. If you ignore this message, the engine will overheat, causing damage and costly repairs. If you encounter this situation, don’t worry, experts from Eurocartool will provide you with detailed solutions in the article below.

What is Mercedes Coolant Warning Light?

Coolant acts as a common bridge transferring heat from the engine to the coolant. During work, the engine will emit a large amount of heat and needs to cool to a specified level. Besides, the operation of other details on the car also creates friction and heat. Coolant will act as a temperature reducer in this operating system.

In addition, coolant also helps protect the engine from damage or wear after long periods of use. If you choose a quality coolant product that is suitable for the type of vehicle you are using, it will help your vehicle operate better and increase its lifespan significantly.


What happens when the coolant level is low Mercedes?

All the heat emitted during vehicle operation will partly be converted into functional energy, partly radiated into the air or into contact details such as cylinders, pistons, engine covers, etc. Therefore, without a car cooling system and coolant to cool down, parts will heat up beyond the allowable temperature, causing many harmful effects such as:

  • Great thermal stress
  • Reduced strength leads to damage to parts
  • High temperatures lose the lubricating effect of lubricants
  • At temperatures of 200-3000 degrees Celsius, lubricating oil will burn, the piston group can get stuck in the cylinder because of expansion, easily causing fire and detonation in gasoline engines.
  • The phenomenon of engine locking and engine block blowing occurs and repair costs will be very large.
  • The lid of the machine is bent or warped.
  • The sealing gasket may be completely damaged.
  • Damaged heat pipes.
  • Damage to piston rings and connecting rod bushings due to high friction.
  • The piston is locked in the cylinder due to expansion due to high temperature.
  • The engine makes a knocking sound.


That’s why coolant plays a very important role, it is the bridge that transfers heat from the engine body to the cooling tank.
If the amount of coolant in the tank does not meet the requirements, a Mercedes coolant warning light will appear on the dashboard.

How to diagnose leaking coolant?

Regularly checking the coolant level will help car owners easily control and add when needed. In addition, this also helps limit the Mercedes coolant warning light display. The steps to perform the check are as follows:
Step 1: Turn off the engine, open the hood, wait for the engine to cool completely.
Step 2: Gently twist the coolant tank cap counterclockwise to release excess pressure and open the cap.
Step 3: If you notice that the coolant level is between the Min and Max lines, it proves that the car still has enough coolant.
Step 4: If the engine coolant level is below the Min line, you need to add more coolant for the vehicle to operate stably.

Instructions to fix the Mercedes coolant warning light?

When the Mercedes coolant warning light is low, you can handle it as follows:

  • Stop the vehicle in a safe location and let the engine cool for at least 30 minutes
  • Open the hood, be careful not to open the radiator cap immediately afterward to avoid boiling coolant splashing out and causing burns.
  • Leave the vehicle in idle mode to wait for the coolant temperature to decrease, causing the warning light to turn off before turning off the engine. Because if the cooling water is turned off right The coolant does not circulate, the fan does not work, so the coolant takes longer to cool.
  • After the engine cools, check to see if there are signs of coolant leakage. If you notice a lack of coolant, add more (you can use pure water as a temporary replacement), then move to the nearest garage for inspection.


Instructions for adding coolant

Step 1: Let the car engine cool completely.
Step 2: Gently twist the car coolant tank cap counterclockwise, then open the cap.
Step 3: If the coolant is below the Min level, slowly add more solution to the specified level, being careful not to overflow the coolant.
Step 4: Twist the cap of the coolant reserve tank until you hear a clicking sound. Be sure to screw the lid so that the arrow on the water tank and the lid are facing each other.

How long can you drive with low coolant levels?

Depending on the purpose of use and the length of the trip, you can drive within a few days from the time the warning light comes on. However, if this condition persists, the engine will overheat and may stop operating.
Our advice is to fill the coolant tank when the Mercedes coolant warning light comes on as soon as possible.

When the Mercedes coolant warning light up on the screen, you should perform a check to refill the tank if necessary. Each type of vehicle will need its own type of coolant, and coolant also has a certain lifespan and needs to be replaced periodically. Follow Eurocartool for more useful car repair and care experiences. Or contact WhatsApp: +13155472355 if you want to receive advice on programming and coding errors on the vehicle.

In addition, if you need support for diagnosis, error reading, coding and programming for Mercedes models, you can contact us for advice and remote repair support through the Technical Support service.

Leave a Reply

Your email address will not be published. Required fields are marked *