Frelander 2. Manual — part 143
Steering Column -
General Specification
Item
Specification
Upper column
Manual column with tilt and reach adjustment
Torque Specifications
Description
Nm
lb-ft
Heatshield lower bolts (2) to steel pinion tower
3.2
2.3
Heatshield upper bolt (1) to plastic seal
2.4
1.77
Steering column bolts
25
18
Steering wheel bolt
48
35
Universal joint to steering gear bolt*
25
18
* New nuts/bolts must be fitted
Steering Column - Steering Column
Description and Operation
COMPONENT LOCATION
Item
Part Number
Description
1
-
Outer bracket
2
-
Energy management plate
3
-
Inner bracket
4
-
Clockspring, steering wheel angle sensor and steering wheel module
5
-
Right Hand (RH) multifunction switch
6
-
Steering wheel
7
-
Left Hand (LH) multifunction switch
8
-
Steering column adjustment lever
9
-
Electric steering column lock
10
-
Upper yoke
11
-
Outer tube
12
-
Inner tube
13
-
Lower yoke
14
-
Clamp bolt
• NOTE: On North American Specification (NAS) vehicles, a running change was introduced during 2008 Model Year (MY) to
disable the electric steering column lock. Under the change, the internal electronics (printed circuit board (PCB), motor,
etc.) of the lock have been removed and the lock has been disabled in the car configuration file. The change is
incorporated on
VIN (vehicle identification number)
082896, 085531, 085622, 085685, 085832, 085891, 085942, 085987,
086049, 086081, 086123, 086178, 086276, 086287, 086309, 086363, 086383, 086389, 086398, 086403 and 091770
onwards.
• NOTE: Items 10, 11, 12 and 13 are components of the intermediate shaft.
OVERVIEW
The steering column is bolted to a magnesium steering column frame which is an integral part of the cross-car beam
located behind the instrument panel. The cross car beam is manufactured from a combination of steel tension members
and ultra-lightweight diecast magnesium carriers. The beam not only forms an armature around which the fascia is
constructed, but is also an integral part of the vehicle's crash structure.
Steering wheel position can be moved by adjusting the column upper for reach or rake, whilst soft-stops are used to
minimize adjustment noise in fore-aft movements. The adjustable upper column is designed to manage crash energy in
the horizontal plane.
The intermediate shaft can collapse telescopically to prevent uncontrolled steering wheel displacement during an impact.
The column lintermediate shaft is produced from steel tube for good rigidity. This is bonded to a stiff thin-walled
elastomer to isolate road noise.
IMPACT PROTECTION
In a serious impact, the steering column is designed to manage two simultaneous events; the intermediate shaft must
isolate the steering wheel from any movement of the steering rack (if the angle of the steering wheel changes it will affect
the way in which the airbag deploys towards the driver).
In addition, to prevent excessive force causing injury as the driver strikes the airbag, the whole upper-column assembly is
designed to progressively move forwards as the driver contacts the airbag. This motion helps to safely and progressively
decelerate the driver. The steering column has a 'Horizontal Load Limiting' system which differs from conventional designs
that rely on movement along the column axis.
Horizontal Load Limiting System
Item
Part Number
Description
A
-
Conventional steering column design
B
-
Horizontal load limiting system
1
-
Mismatch between direction of force and motion
2
-
Motion aligned to force
The Horizontal Load Limiting System provides a progressive and stable load limiting characteristic as shown in 'B' in the
illustration. Loads applied to the column cause the column to move horizontally with the driver. This movement is
controlled by an energy management plate. The plate has leaves which peel back in a controlled manner, absorbing energy
and allowing the column to move with the driver.
The plate is bolted to the steering column outer bracket attached to cross-car beam and the inner bracke
Pyrotechnic Additional Load Device - North American Specification (NAS) Only
• NOTE: Steering column shown deployed for clarity
Item
Part Number
Description
1
-
Energy management plate
2
-
Pin
3
-
Pyrotechnic device
4
-
Electrical connector
On NAS market vehicles, an additional pyrotechnic device is fitted to provide increased energy absorption to allow for a
driver not wearing a seat belt. If the driver is wearing a seatbelt and a crash situation occurs, the device is not activated.
The pyrotechnic device is located below the energy management plate. W hen the system detects that the driver's seat
belt is not buckled, and a crash situation occurs which activates the airbags, the device fires, which retracts the pin
engaged in a hole in the central leaf in the energy management plate. This provides the required increase in energy
absorption to allow for the additional loading caused by the unrestrained driver.
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