Please note the following points to prevent the vehicle from rolling back unintentionally on a gradient.
Pull and hold the switch
and press the accelerator. The parking brake will remain engaged and prevent any tendency to roll back down the slope.
You can release the switch
as soon as the engine is delivering enough power to the wheels.
Depending on the weight of the vehicle and trailer and the steepness of the slope, there may be a tendency to roll back downhill when driving away from a standstill. You can prevent this by pulling out and holding the switch
as you press the accelerator (in the same way as with a conventional handbrake).