Lift up on the auto up driver window switch.
Mercedes lock door with engine running.
Only way i know how.
Original poster 1 point 3 years ago.
To do this fully close the sliding door once with the button on the centre console or in the doorway pressed down.
The engine might not be running when the car is first parked but will come on later as the car s batteries run down.
Pull your arm out of the car before it gets pinched by the closing window.
Roll down the drivers side window.
Drivers can lock and unlock the car just by touching the door handles.
Lock works perfectly now.
Ive done it by starting the car open drivers door hit lock button on door then use metal key inside fob to manually lock the driver door.
Reach inside and hit the power lock switch and lock the doors.
On those models the door lock actuators may fail causing the door lock to bounce up and down several times.
They found that there was a loose wire inside my door.
Open the door and exit the car.
Then briefly press one of the buttons to completely open and close the door once.
If you turn the key from man position back to auto you must reset the sliding door.
There is a couple of ways to fix this problem.
Mercedes benz vehicles such as e c s ml gl r class are designed to automatically lock the doors as soon as you start to drive.