Start/Stop function

Start/Stop is a function that temporarily switches off the engine when the vehicle has stopped, e.g. at a traffic light or in heavy traffic, and then starts it again automatically when needed.

The Start/Stop function reduces fuel consumption, which can in turn contribute to an environmentally conscious driving style and reduced emissions.

To keep in mind when using the Start/Stop function

Certain conditions must be met for Start/Stop to function.

The Start/Stop function is not activated

The engine may not switch off/the function may not be activated due to one or more of the following criteria:

  • the driver has not fastened their seat belt
  • the vehicle has not reached a speed of about 10 km/h (6 mph) after start or after the function has been activated a number of times in succession
  • the engine has not reached its normal operating temperature
  • the ambient temperature is under approximately -5 °C (23 °F) or over approximately 37 °C (98 °F)
  • windshield heating is activated
  • the climate system settings and the actual climate in the passenger compartment differ
  • the driver is making large steering wheel movements
  • the road gradient is very steep
  • the hood is open
  • ABS has been activated
  • hard braking (even if the ABS system has not been activated)
  • the start battery's charge has dropped below the minimum level
  • many starts during a short period of time have triggered the starter motor's overheating protection
  • the exhaust system's particulate filter is full
  • a trailer is connected to the vehicle's electrical system.

 Note

High electrical current consumption may cause the battery level to become low, which will temporarily limit the Start/Stop function. The engine will then start automatically without the driver lifting their foot from the brake pedal.

For vehicles with manual transmissions, the Start/Stop function is deactivated without the clutch being depressed if the gear selector is in neutral. The start/stop function will become available again when the battery level is sufficiently high.

The Start/Stop function is not deactivated

The engine may not start/the function may not be deactivated due to one or more of the following criteria:

  • the driver has not fastened their seat belt
  • gear selector position P is engaged and the driver's door is open.

The Start/Stop function is deactivated without the brake pedal being released

The function may be deactivated and the engine may start without the driver releasing the brake pedal in the following cases:

  • high levels of condensation on the inside of the windows
  • the climate system settings and the actual climate in the passenger compartment differ
  • the brake pedal is pumped repeatedly
  • the hood is open
  • the start battery's charge has dropped below the minimum level
  • the driver's seat belt is unbuckled and the gear selector is in position D or N
  • the gear selector is moved from position D to R or M
  • the driver's door is open with the gear selector in position D.

 Warning

Do not open the hood when the Start/Stop function is active. Switch off the engine normally before raising the hood.

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