Manual: 2013/2014 911

Page: 163

HOLD function: Drive-Off Assistant, Standstill Management
The HOLD function, as an assistance function, assists the driver when stopping and driving off on upward slopes.

The vehicle is automatically prevented from rolling back away from the desired direction of travel.

When the HOLD function is active, the indicator light on the instrument panel comes on.

Driving off with the Drive-Off Assistant on vehicles with manual transmission

  1. Hold the vehicle securely on the slope with the footbrake.
    The engine must be running.
  2. Press the clutch pedal fully.
  3. Engage a gear corresponding to the direction of travel up the slope (1st gear or reverse gear).
  4. Release the footbrake while keeping the clutch pedal pressed.
    The vehicle is held on the slope to facilitate driving off and prevent it from rolling back.
  5. Drive off as usual.

Information
If the vehicle is held on the slope by the electric parking brake, drive off in the usual way.

The electric parking brake detects the driver's intention to drive off and is released automatically.

For information on the electric parking brake:

  • Please see the chapter "ELECTRIC PARKING BRAKE" on page 142.

Information
The Drive-Off Assistant will not function:
– If the clutch is not pressed.
– If the vehicle is not stationary.
– If the engine is not running.
– On gradients of less than 5 %.
– If the pressure on the brake pedal is too low.


Standstill management on vehicles with PDK transmission
The vehicle is stopped and prevented from rolling back away from the desired direction of travel even without pressing the brake.

Information
The HOLD function is not available on vehicles with PDK transmission if the PDK selector lever is in position N.

If the PDK selector lever is moved while the HOLD function is active, the HOLD function is deactivated.


If the driver's seat belt is unfastened and the driver's door is opened while the HOLD function is active, the electric parking brake is activated automatically.

For information on the electric parking brake:

  • Please see the chapter "ELECTRIC PARKING BRAKE" on page 142.

Limits of HOLD Function

The limits set by the physics of driving cannot be overcome, even with the HOLD function.

Responsibility for driving off on upward slopes is still the driver's, despite the HOLD function.

Assistance by the HOLD function is not always guaranteed when stopping and driving off on a slippery surface (e.g. on icy or loose surfaces).

In this case, the vehicle can slip.

  • Always adjust your driving style to the driving conditions and vehicle load. Use the footbrake if necessary.

Drive-Off Assistant Not Working

If the Drive-Off Assistant is not functioning, the driver cannot be assisted when driving off on hills.

  • Hold the vehicle with the footbrake.

Vehicle Roll-back

If the vehicle comes to a standstill on a steep uphill gradient without operation of the footbrake by the driver, this may result in a certain roll-back before the vehicle is held by the HOLD function. In this situation, the roll-back can be reduced by pressing the footbrake.

  • Assist holding of the vehicle by increasing the braking force with the footbrake.

Brake pedal feels different

When the HOLD function is active, the brake pedal may feel different and you may hear hydraulic noises.

This behavior is normal for the system. It is not a fault.