Engine

Problem Possible causes/consequences and Solutions
yellow Check

The yellow Check Engine warning lamp lights up while the engine is running.

 There may be a malfunction, for example:
• in the engine management
• in the fuel injection system
• in the exhaust system
• in the ignition system
• in the fuel system

The emission limit values may be exceeded and the engine may be running in emergency mode.
soon as possible at a qualified Have the vehicle checked as soon as possible at a qualified specialist workshop.

required by law to immediately visit a In some states, you are required by law to immediately visit a qualified specialist workshop as soon as the yellow Check Engine warning lamp lights up. If in doubt, check whether such legal regulations apply in the state/province in which you are currently driving.
yellow reserve fuel

The yellow reserve fuel warning lamp flashes while the vehicle is in motion. In addition, the yellow Check Engine warning lamp may light up. may light up.

 The fuel system pressure is too low. The fuel filler cap is not closed correctly or the fuel system is leaking.
display messages in the multifunction Observe the additional display messages in the multifunction display.
cap is correctly closed. Check that the fuel filler cap is correctly closed.
is not correctly closed: close the fuel filler If the fuel filler cap is not correctly closed: close the fuel filler cap.
is closed: visit a qualified specialist If the fuel filler cap is closed: visit a qualified specialist workshop.
yellow reserve fuel

The yellow reserve fuel warning lamp lights up while the engine is running.

 The fuel level has dropped into the reserve range.
station. Refuel at the nearest gas station.
coolant

The red coolant warning lamp lights up while the engine is running and the coolant temperature gauge is at the start of the scale.

 The temperature sensor for the coolant temperature gauge is defective.
The coolant temperature is no longer being monitored. There is a risk of engine damage if the coolant temperature is too high.
vehicle safely and switch off the engine, Pull over and stop the vehicle safely and switch off the engine, paying attention to road and traffic conditions. Do not continue driving under any circumstances.
Consult a qualified Apply the parking brake.
specialist workshop. Consult a qualified specialist workshop.
coolant

The red coolant warning lamp comes on while the engine is running.

 The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may be blocked or the electric engine radiator fan may be malfunctioning.
The coolant is too hot and the engine is no longer being cooled sufficiently.
display messages in the multifunction Observe the additional display messages in the multifunction display.
vehicle safely and switch off the engine, Pull over and stop the vehicle safely and switch off the engine, paying attention to road and traffic conditions.
coolant to cool. Allow the engine and coolant to cool.
add coolant. Observe Check the coolant level and add coolant. Observe the warning notes.
more often than usual, have the If you need to add coolant more often than usual, have the engine coolant system checked.
supply to the engine radiator is not Make sure that the air supply to the engine radiator is not blocked, e.g. by snow, slush or ice.
under 248 °F (120 °C ), drive to the next At coolant temperatures under 248 °F (120 °C ), drive to the next qualified specialist workshop.
to heavy loads, e.g. driving in Avoid subjecting the engine to heavy loads, e.g. driving in mountainous terrain, and stop-and-go traffic.
coolant

The red coolant warning lamp comes on while the engine is running. A warning tone also sounds.

 The coolant temperature has exceeded 248 °F (120 °C ). The airflow to the engine radiator may be blocked or the coolant level may be too low.
The engine is not being cooled sufficiently and may be damaged.
display messages in the multifunction Observe the additional display messages in the multifunction display.
vehicle safely and switch off the engine, Pull over and stop the vehicle safely and switch off the engine, paying attention to road and traffic conditions.
coolant to cool. Allow the engine and coolant to cool.
add coolant. Observe Check the coolant level and add coolant. Observe the warning notes.
more often than usual, have the If you need to add coolant more often than usual, have the engine coolant system checked.
supply to the engine radiator is not Make sure that the air supply to the engine radiator is not blocked, e.g. by snow, slush or ice.
under 248 °F (120 °C ), drive to the next At coolant temperatures under 248 °F (120 °C ), drive to the next qualified specialist workshop.
to heavy loads, e.g. driving in Avoid subjecting the engine to heavy loads, e.g. driving in mountainous terrain, and stop-and-go traffic.

WARNING
Driving when your engine is overheated can cause some fluids which may have leaked into the engine compartment to catch fire. You could be seriously burned.
Steam from an overheated engine can cause serious burns which can occur just by opening the engine hood. Stay away from the engine if you see or hear steam coming from it.
Stop the vehicle in a safe location away from other traffic. Turn off the engine, get out of the vehicle and do not stand near the vehicle until the engine has cooled down.

exceeds 248 °F (120 °C ) do not continue driving. The engine will If the coolant temperature exceeds 248 °F (120 °C ) do not continue driving. The engine will otherwise be damaged.

    See also:

    Information for customers in California
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    Call priority
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