Mercedes E-Class: Engine

The engine section of the Mercedes E-Class (4th generation, W212, 2009–2016) describes warning messages that indicate critical conditions such as low coolant or engine overheating. These notes help prevent engine damage and ensure the vehicle remains safe to operate. Practical recommendations support safe handling in emergency situations.

Display messages	Possible causes/consequences and solutions
Top up coolant, see Owner's Manual	The coolant level is too low. Avoid longer trips with insufficient coolant in the engine cooling system. Otherwise the engine may be damaged. Top up coolant and observe the warning notes. If coolant must be topped up frequently, have the engine cooling system checked at a qualified workshop.
	The fan motor is defective. At coolant temperatures below 120, drive on only as far as the next qualified workshop. Avoid high engine loads while doing so, e.g. driving uphill and stop-and-go traffic.
Coolant Stop engine	The coolant is too hot. A warning tone also sounds. WARNING Do not drive with an overheated engine. Fluids that have leaked or spilled into the engine compartment could ignite. Steam from an overheated engine can also cause severe burns, even if only the hood is opened. There is a risk of injury! Stop safely as soon as possible and switch off the engine. Secure the vehicle against rolling away. Wait until the engine has cooled down. Make sure the airflow to the radiator is not blocked, e.g. by frozen slush. Wait until the display message goes out and the coolant temperature is below 120°C, then restart the engine. Otherwise the engine may be damaged. Monitor the coolant temperature gauge. If the temperature rises again, go to a qualified workshop immediately. During normal driving and with the correct coolant level, the display may rise to 120 °C.
see Owner's Manual	The battery is not charging. A warning tone also sounds. Possible causes: defective alternator torn serpentine belt a fault in the electrical system Do not continue driving. The engine may otherwise overheat. Stop safely as soon as possible and switch off the engine. Secure the vehicle against rolling away. Contact a qualified workshop.
Stop, see Owner's Manual	The battery is not charging and its state of charge has become too low. A warning tone also sounds. Stop safely as soon as possible and switch off the engine. Secure the vehicle against rolling away. Follow the instructions for the display messagesee Owner's Manual. Contact a qualified workshop.
Start engine, see Owner's Manual	The engine is switched off and the battery state of charge is too low. Switch off unneeded electrical consumers, e.g. rear window heater and interior lighting. Let the engine run for a few minutes or drive a longer distance. The battery is charging.
Check engine oil level at next refuelling stop	The engine oil level has dropped to the minimum. A warning tone also sounds. Avoid longer trips with insufficient engine oil. Otherwise the engine may be damaged. Check the engine oil level at the next refuelling stop at the latest. If necessary, top up engine oil. If engine oil has to be topped up frequently, have the engine checked at a qualified workshop. You can obtain information on approved engine oils at any qualified workshop or online at .
At next refuelling stop, top up 1 litre of engine oil	AMG vehicles: The engine oil level is too low. Avoid longer trips with insufficient engine oil. Otherwise the engine may be damaged. Check the engine oil level at the next refuelling stop at the latest. If necessary, top up engine oil. If engine oil has to be topped up frequently, have the engine checked at a qualified workshop. You can obtain information on approved engine oils at any qualified workshop or online at .
Engine oil level Stop engine	The engine oil level is too low. The engine may be damaged. Stop safely as soon as possible and switch off the engine. Secure the vehicle against rolling away. Check engine oil level. If necessary, top up engine oil.
Fuel reserve	The fuel supply has reached the reserve range. Auxiliary heater operation is deactivated in the reserve range. Refuel at the next filling station.
	There is very little fuel left in the fuel tank. Auxiliary heater operation is deactivated. Be sure to refuel at the next filling station.
Replace air filter	Diesel vehicles: The engine air filter is dirty and must be replaced. Consult a qualified specialist workshop.
Clean fuel filter	Diesel vehicles: There is water in the fuel filter. The water must be drained. Consult a qualified specialist workshop.
Top up AdBlue at workshop, see Owner's Manual	The AdBlue supply has dropped below the reserve mark. A warning tone also sounds. Have AdBlue topped up at a qualified workshop as soon as possible.
Top up AdBlue at workshop No start in ..km	The AdBlue supply is only sufficient for the distance shown. A warning tone also sounds. Have AdBlue topped up at a qualified workshop immediately.
Top up AdBlue at workshop No start possible	The AdBlue supply is empty. A warning tone also sounds. You cannot start the engine. Contact a qualified workshop immediately.
Check AdBlue, see Owner's Manual	The AdBlue system is faulty. A warning tone also sounds. Consult a qualified specialist workshop.
No start in ..km	The AdBlue system is faulty. A warning tone also sounds. Visit a qualified workshop immediately.
No start possible	The AdBlue system is faulty. A warning tone also sounds. You cannot start the engine. Contact a qualified workshop immediately.

The engine indicators of the Mercedes E-Class W212 (model years 2009–2016) help you operate the engine safely. Coolant temperature, oil level or battery charge – all values are monitored to prevent damage to the drivetrain.

The messages in the display and the accompanying warning signals allow the driver to react in time. This keeps the engine operating safely, even in difficult situations.

Engine

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