Electric Steering Column Adjustment (ELE), Function - GF46.15-P-0004GN
Model 166
as of model year 2016
with code 275 (Memory Package (driver's seat, steering column and mirror))
Model 292
with code 275 (Memory Package (driver's seat, steering column and mirror))
Electrically adjustable steering column, general
The electrically adjustable steering column function allows the steering column to be adjusted as required and increases comfort when getting into and out of the vehicle.
The electrically adjustable steering column function includes the following subfunctions:
- Function sequence for normalization
- Function sequence for setting steering column and storing position
- Function sequence for easy entry/exit
Function sequence for normalization
Normalization is the basis for assignment of the current position of the steering wheel relative to the steering column position as detected by the driver's seat Control unit. Normalization must be performed during initial startup or in a denormalized condition. The following mechanical stops have to be moved to for the normalization procedure:
- Front end stop
- Upper stop
Normalization during initial commissioning is conducted using the diagnosis tester. Circuit 15R must be switched on here.
After denormalization, normalization can be performed using the adjustment function. To do so, press and hold the steering column adjustment switch after reaching the mechanical end stops for another t = 250 ms.
The steering column tube module Control unit reads in the switch position of the steering column adjustment switch directly and sends it via chassis CAN 1, the electronic ignition lock Control unit and interior CAN to the driver seat Control unit. The driver seat Control unit directly actuates the corresponding steering column adjustment motor, reads in the signals directly from the respective steering column Hall sensor and evaluates these signals. Upon successful normalization, the driver's seat Control unit switches off the corresponding steering column adjustment motor.
Function sequence for setting steering column and storing position
The function enables various steering column positions to be adjusted, stored and called up. The adjust steering column and save position function includes the following subfunctions:
- Adjust steering column function sequence
- Function sequence for save position of steering column
- Function sequence for call up saved steering column position
Adjust steering column function sequence
The steering column is adjusted by operating the steering column adjustment switch.
The steering column tube module Control unit reads in the switch position of the steering column adjustment switch directly and sends it via chassis CAN 1, the electronic ignition lock Control unit and interior CAN to the driver seat Control unit.
The driver seat Control unit directly actuates the corresponding steering column adjustment motor, reads in the signals directly from the respective steering column Hall sensor and evaluates these signals. Actuation takes place as long as the steering column adjustment switch is operated or until an end position is reached.
Function sequence for save position of steering column
The current position of the steering column can be saved together with the adjustment of the driver seat and the outside mirrors.
The steering column position is defined by the signals of the steering column Hall sensors. It is stored using the left front seat adjustment switch group.
The following options are available for saving:
- Operate and hold the left front memory function switch, then press the memory switch 1, 2 or 3.
- Press left front memory function switch for t > 100 ms and release, then press the memory switch 1, 2 or 3 within t ≥ 0.2 to 3 s.
The left front door Control unit reads in the status of the corresponding switches in the left front seat adjustment switch group via the left front door LIN and sends the "Store memory position" request via the interior CAN to the driver seat Control unit. The driver's seat Control unit uses the signals from the steering column Hall sensors to save the current position of the steering column. Up to 3 different positions can be saved.
When the position of the steering column has been successfully stored, an acknowledgment tone is output by the instrument cluster. The request for this is sent by the drivers eat Control unit over the interior CAN to the instrument cluster.
Function sequence for call up saved steering column position
Press and hold memory switch (1, 2 or 3) until the stored setting is reached.
Releasing leads to immediate termination of the adjustment procedure.
The left front door Control unit reads in the status of the respective memory switch via the left front door LIN and sends this status via the interior CAN to the driver seat Control unit. The driver seat Control unit actuates the steering column adjustment motors directly. The signals from the steering column Hall sensors are read in directly by the driver seat Control unit.
Additional function requirements for easy entry/exit
- Easy entry/exit activated via instrument cluster
Function sequence for easy entry/exit
The steering column is moved upwards before entering or exiting the vehicle and makes it easier for the driver to enter or exit the vehicle. The easy entry/exit function can be switched on and off via the "Settings" menu in the instrument cluster. The corresponding selection is made using the multi function steering wheel button groups. The steering wheel electronics reads in the Control signals on the multifunction steering wheel button groups directly and transmit them to the steering column tube module Control unit over the steering LIN. The steering column tube module Control unit sends the Control signals of the multifunction steering wheel button group over chassis CAN 1, electronic ignition lock Control unit and chassis CAN 2 to the instrument cluster.
The instrument cluster sends the status of the easy entry/exit function to the driver seat Control unit via interior CAN.
The easy entry and exit feature function includes the following subfunctions:
- Function sequence for move to easy entry/exit position
- Function sequence for "Move to driving position"
- Function sequence for repeat limiter
- Function sequence for crash-active steering column adjustment
Function sequence for move to easy entry/exit position
The function is triggered when circuit 15C is switched off or the driver door is opened with circuit 15C or 15R ON. The electronic ignition lock Control unit sends the circuit 15 status over the interior CAN to the driver's seat Control unit. The left front door Control unit sends the status of the left front door (open or closed) over interior CAN to the driver seat Control unit.
The driver seat Control unit reads in all relevant information, stores the current position of the steering column (driving position) and actuates the steering column up/down adjustment motor accordingly. The signals of the steering column up/down Hall sensor are read in directly by the driver seat Control unit.
Function sequence for "Move to driving position"
The driver seat Control unit actuates the steering column up/down adjustment motor under the following conditions in order to return the steering column to the driving position:
- Closing driver door with circuit 15 On
- Change from circuit 30 to circuit 15C with driver door closed
- Change from circuit 15C to circuit 15R with driver door closed
- Change from circuit 15R to circuit 15 ON with driver door closed
The electronic ignition lock Control unit sends the circuit 15 status over the interior CAN to the driver's seat Control unit.
The left front door Control unit sends the status of the left front door (open or closed) over interior CAN to the driver seat Control unit. The driver seat Control unit reads in all relevant information and actuates the steering column up/down adjustment motor to match the stored data. The signals of the steering column up/down Hall sensor are read in directly by the driver seat Control unit.
The "Move to entry/exit position" or "Move to driving position" functions are aborted under the following conditions:
- Undervoltage or overvoltage
- Manual adjustment request over the steering column adjustment switch
- Memory adjustment request
- Reversal of circuit 15 transition or driver door status change
- Defect of steering column up/down Hall sensor integrated into steering column up/down adjustment motor
Function sequence for repeat limiter
In order to prevent the steering column up/down adjustment motor from overloading in the case of repeated switching on/off of the "Move to entry/exit position" and "Move to driving position" functions, the number of adjustment cycles is limited to five only. This is reset as soon as the electronic ignition lock Control unit sends the status of circuit 15R or if the left front door Control unit sends the "Driver door open" or "Driver door closed" status.
Function sequence for crash-active steering column adjustment
Following the occurrence of a crash event the driver seat and the steering column are automatically moved upwards to a defined position. The supplemental restraint system Control unit transmits the crash signal via chassis CAN 1, electronic ignition lock Control unit and interior CAN to the driver seat Control unit. The driver seat Control unit then actuates the steering column adjustment up/down motor accordingly. The signals of the steering column up/down Hall sensor are read in directly by the driver seat Control unit.
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