Mercedes-Benz B-Class Quiz
Driving and parking

Engine problems

In this manual: Driving and parking
Introduction — 16At a glance — 11Safety — 27Opening and closing — 33Seats, steering wheel and mirrors — 21Lighting and windshield wipers — 25Air conditioning — 27Driving and parking — 66On-board computer and displays — 35Storage and other — 21Maintenance and care — 10Flat tire assistance — 26Wheels and tires — 26Technical data — 22
~3min read
Problem Possible causes/consequences and solutions
The engine does not start. The HOLD function or DISTRONIC PLUS is activated.
  • Deactivate the HOLD function or DISTRONIC PLUS.
  • Restart the engine.
The engine does not start. You can hear the starter motor turning.
  • The engine electronics have failed.
  • The fuel supply has failed.
  • Before attempting to start again, turn the key back to position 0 in the ignition switch.
  • Restart the engine. However, be careful not to discharge the battery through long and repeated attempts.

If the engine still does not start after several attempts:

  • Contact a qualified workshop.
The engine does not start. You can hear the starter motor turning. The low fuel warning lamp is lit and the fuel gauge shows 0. You have driven until the tank was completely empty.
  • Refuel.
The engine does not start. You cannot hear the starter motor turning. The on-board voltage is too low (battery voltage too low or battery discharged).
  • Try jump-starting

If the engine still does not start with jump-starting:

  • Contact a qualified workshop.

The starter motor has been subjected to excessive thermal stress.

  • Let the starter motor cool for approx. 2 minutes.
  • Restart the engine.

If the engine still does not start:

  • Contact a qualified workshop, for example a Mercedes-Benz service center.
Vehicles with a gasoline engine: The engine runs unevenly and misfires The engine electronics or a mechanical element of the engine management system has failed.
  • Accelerate only lightly.

Otherwise, unburned fuel may reach the catalytic converter and damage it.

  • Have the cause of the problem rectified immediately by a qualified workshop.
The coolant temperature gauge shows a temperature above 120 °C.En outre, le voyant d'alerte du liquide de refroidissement peut s'allumer.
In addition, the coolant warning lamp may light up and a warning signal may sound.		 The coolant level is too low. The coolant is too hot and the engine is not sufficiently cooled.
  • Stop the vehicle as soon as possible and let the engine and coolant cool down.
  • Check the coolant level. Observe the warnings for this, and top up the coolant if necessary.

If the coolant level is correct, the electric cooling fan of the engine radiator may be faulty. The coolant is too hot and the engine is not being cooled sufficiently.

  • If the coolant temperature is below 120jusqu'à l'atelier qualifié le plus proche, continue driving
    to the nearest qualified workshop
  • In this case, avoid placing a heavy load on the engine (for example, driving in mountains or in heavy traffic).

Test yourself

A quick Mercedes-Benz B-Class quiz: every answer comes with an explanation and a link to the manual page.