Problems with the engine

Problem Possible causes/consequences and Solutions
The engine does not start. The starter motor can be heard. - There is a malfunction in the engine electronics.
- There is a malfunction in the fuel supply.

- Try to start the engine again. Avoid excessively long and frequent attempts to start the engine as these will drain the battery.

If the engine does not start after several attempts:
- Consult a qualified specialist workshop, e.g. an authorized Mercedes-Benz Center.
The engine does not start. You cannot hear the starter motor. The on-board voltage is too low because the battery is too weak or discharged.
- Jump-start the vehicle.
If the engine does not start despite attempts to jump-start it:
- Consult a qualified specialist workshop, e.g. an authorized Mercedes-Benz Center.
The starter motor was exposed to a thermal load that was too high.
- Allow the starter motor to cool down for approximately two minutes.
- Try to start the engine again.
If the engine still does not start:
- Consult a qualified specialist workshop, e.g. an authorized Mercedes-Benz Center.
The engine is not running smoothly and is misfiring. There is a malfunction in the engine electronics or a mechanical component of the engine management system.
- Only depress the accelerator pedal slightly.
- Have the cause rectified immediately at a qualified specialist workshop, e.g. an authorized Mercedes-Benz Center.
Otherwise, non-combusted fuel may get into the catalytic converter and damage it.
The coolant temperature gauge shows a value above 248 °F (120 °C). The coolant level is too low. The coolant is too hot and the engine is no longer being cooled sufficiently.
- Stop as soon as possible and allow the engine and the coolant to cool down.
- Check the coolant level. Observe the warning notes as you do so and add coolant if necessary.
    See also:

    Important safety notes
    WARNING Never switch off the engine while the vehicle is in motion. There is no brake boost for the service brake if the engine is not running. If the ignition is switched off, there is also ...

    Instruction labels for tires and loads
    WARNING Do not overload the tires by exceeding the specified load limit as indicated on the Tire and Loading Information placard on the driver's door B-pillar. Overloading the tires can ove ...

    Engine number
    Emission control information plate, including the certification of both federal and Californian emissions standards Engine number (stamped into the crankcase) VIN (on the lower edge of the ...