Conditions that require a manual engine start
The engine must be started manually under the following conditions:
•If the driver door is opened.
•If the bonnet is opened.
Activating and deactivating the start/stop system manually
•Press the button  in the centre console ⇒ Fig. 121 to deactivate the system. If the 
start/stop system has been deactivated, the indicator lamp in the button lights up.
•Press the button  in the centre console again ⇒ Fig. 121 to reactivate the system.
The instrument cluster shows the status of the start/stop system every time the  button is 
pressed.
If the start/stop system has switched the engine off, it will start again as soon as the system has 
been deactivated manually with the  button.
Always deactivate the start/stop system manually when driving through water.
Start/stop mode when Adaptive Cruise Control (ACCyf  L V  D F W L Y e
The engine will be switched off after the Adaptive Cruise Control (ACCyf  K D V  E U R X J K W  W K H  Y H K L F O H  W R  D  
standstill via an active braking intervention ⇒ Adaptive Cruise Control (ACCyf.
m/k/a995MKVehicles with DSG dual clutch gearbox: when the Adaptive Cruise Control 
(ACCyf  L V  D F W L Y H   W K H  ' 6 G dual clutch gearbox can shift into coasting mode and the engine can be 
switched off with the engine-off coasting function.
In the following instances, the engine will restart when the Adaptive Cruise Control (ACCyf  L V  D F W L Y H :
•If the accelerator is depressed.
•When the Adaptive Cruise Control (ACCyf  K D V  U H V X P H G  V S H H G  D Q G  D X W R P D W L F  G L V W D Q F H  F R Q W U R O .
•If the vehicle ahead has moved on.
•If the Adaptive Cruise Control (ACCyf  L V  G H D F W L Y D W H G  D Q G  W K H  Y H K L F O H  G U L Y L Q J  L Q  I U R Q W  P R Y H G  D Z D \ .
Troubleshooting
The engine stop function may be deactivated if the temperature is above around 38°C (100°Fyf .
In some cases, it may be necessary to restart the engine manually. Follow any 
corresponding messages on the instrument cluster display.
The start/stop function is activated automatically if the Eco driving profile is selected on 
vehicles with driving profile selection ⇒ Driving profile selection and 4MOTION Active Control.
Always deactivate the start/stop system manually when driving through water.
Manual gearbox: selecting a gear
®
Never switch off the engine or the ignition while the vehicle is in motion. This can lead to a 
loss of vehicle control, accidents and serious injuries.
•The airbags and belt tensioners will not work if the ignition is switched off.
•The brake servo will not work when the engine is switched off. That is why more 
pressure on the brake pedal is needed to brake the vehicle when the engine is 
switched off.
•The power steering will not work when the engine is not running. More power is 
needed to steer the vehicle when the engine is switched off.
•When the ignition is switched off, the steering lock may activate and you will no longer 
be able to steer the vehicle.
•The start/stop system must be deactivated if work is to be carried out in the engine 
compartment.
WARNING
If the start/stop system is used in very high outside temperatures over a long period, the 
12-volt vehicle battery can be damaged.
NOTICE