BMW 7 Series: Functions

Automatic Soft Close

The Automatic Soft Close function is an autonomous function. The only connection to the car's electrical system is Terminal 30 basic mode (Terminal 30B) and the ground connection. The Automatic Soft Close function is operational as of "Terminal 30B ON".

Circuit Diagram for an Automatic Soft Close System

The electronics for controlling and monitoring the function are located in the Automatic Soft Close function drive.

The sensors for the Automatic Soft Close function are Hall-effect sensors and are located in the locks. The Hall sensors are built into the lock of each vehicle door. One Hall sensor is for the locking pawl, the other for the rotary striker.

Fig. 18: Automatic Soft Close System Circuit Diagram

COMPONENTS DESCRIPTION CHART

1. Lock in the vehicle door
2. Automatic Soft Close function drive
3. Automatic Soft Close function drive motor
4. Locking pawl Hall sensor
5. Rotary striker Hall sensor

The Automatic Soft Close function analyzes the status of the Hall sensors. The Automatic Soft Close drive units are operated or moved back to their starting position according to status.

The Automatic Soft Close function drive is connected to lock by way of a Bowden cable and a 3 wire cable.

The following illustration shows where the Automatic Soft Close function drives are fitted.

Fig. 19: Location Of F01/F02 Automatic Soft Close System

COMPONENTS DESCRIPTION CHART

1. Drive for Automatic Soft Close function in driver's side door
2. Lock for driver's side door
3. Drive for Automatic Soft Close function in driver's side rear door
4. Lock for driver's side rear door

Locking Procedure when Door is Pushed into the Lock

Starting position: Door open, the Automatic Soft Close function is in the standby position.

When the door is closed normally, first the locking pawl (lock) Hall sensor changes its status. The electronics in the Automatic Soft Close function drive start the door closing operation after a delay of 200 ms. This prevents the Automatic Soft Close drive unit starting before the lock bolt is located in the rotary striker. The drive operates the rotary striker by way of the Bowden cable until the Hall sensor for the rotary striker changes its status. The locking pawl is then engaged and secured in the rotary striker. Operation of the Automatic Soft Close drive unit is then stopped and the Automatic Soft Close drive unit returns to its parked position.

When the door is opened using the outside door handle (bow handle) or inside door handle, the system runs back to its original position. This is also known as the standby position.

NOTE: Only when the rotary striker sensor has changed its status is the rotary striker mechanically locked by the locking pawl. This is particularly important, as only then is it guaranteed that the door is truly closed.

Closing the Door by Slamming

Slamming the door would make closing with the Automatic Soft Close function drive unnecessary. However, since it is essential to ensure that the door is definitely closed, the Automatic Soft Close drive unit is nevertheless still operated for safety reasons.

The electronic circuitry in the Automatic Soft Close drive unit detects the slamming of the door by the fact that the locking pawl and rotary striker Hall-effect sensors have changed their status within a short time.

Anti-repeat Circuit

Every Automatic Soft Close function drive has an anti-repeat circuit to prevent overheating of the Automatic Soft Close function drive. It permits 15 operations (counter incriminated up to 15 times) of the control for the Automatic Soft Close function drive. The Automatic Soft Close function drive is then locked electrically for approximately 2 minutes.

Design of the Lock and Drive

Fig. 20: Identifying Lock And Drive Design

COMPONENTS DESCRIPTION CHART

1. Rotary striker
2. Rotary striker pull pawl
3. Advance detent tooth for rotary striker
4. Drive pawl
5. Automatic Soft Close function drive actuating lever
6. Locking pawl
7. Rotary striker main detent tooth
8. Hall sensor installation locations

Light closing causes the advance detent tooth (3) of the rotary striker (1) to engage on the locking pawl (6). The Automatic Soft Close function drive pulls on the actuating lever (5). The actuating lever rotates the rotary striker by means of the pull latch (4) until it is rotated over the main detent tooth (7). The locking pawl can now engage in the main detent tooth of the rotary striker. The rotary striker is thus secured and the lock can no longer open by itself.

Fig. 21: Basic Principle Of Automatic Soft Close Drive Unit (E70)

COMPONENTS DESCRIPTION CHART

1. Bowden cable
2. Control electronics
3. Bowden cable drive wheel
4. Drive worm
5. Idler gear
6. Drive motor

The Automatic Soft Close function drive motor (6) has a two-start worm (4) on its shaft. This permits drive in the CLOSE direction for the Automatic Soft Close function. The rotary motion of the drive worm is transferred to the driven wheel (3) by the idler gear (5). The drive gear transfers the rotary motion to the Bowden cable (1).

This means that the actuating lever in the lock is pulled by the Bowden cable and thus the vehicle door is fully closed.

SERVICE INFORMATION

Lock and Drive

The lock and the Automatic Soft Close function drive are a closed unit (modular). This means that a faulty lock or Automatic Soft Close function drive cannot be replaced individually. Opening the drive, for instance, destroys it, and perfect operation is no longer guaranteed. The Automatic Soft Close function drive is inseparably fastened to the lock. The lock and the Automatic Soft Close drive unit can only be ordered together as spare parts.

NOTE: There is no diagnostic function for the Automatic Soft Close function drive in the diagnostics system. Retrofitting the Automatic Soft Close system would be very complicated and is therefore not envisaged.

There is no diagnostic function for the Automatic Soft Close function drive in the diagnostics system.

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