Land Rover Defender: Seatbelt System - Description

FRONT ROW SEATBELTS

The outer of the front seatbelt retractors are attached to the vehicle body on the lower B-pillar. The webbing runs from the retractor, through the seatbelt D-loop which is installed on the upper B-pillar, to an anchor point. The anchor point is located at the base of the seat frame.

The center of front row seatbelt retractor is installed in the center seat frame. The webbing runs from the retractor over the seat. The anchor is installed through the retention trim. The anchor point is located at the base of the seat frame.

SECOND ROW SEATBELTS

The retractor of each side second row seatbelt is attached to the body immediately behind the C-pillar lower. The webbing runs from the retractor, through a D-loop located on the upper C-pillar. The anchor point is located on the rear floor at the front of related wheel arch.

The retractor for the center second row seatbelt is installed in the top of the seat backrest. The webbing runs from the retractor, over the top of the seat. An anchor point is located at the base of the seat frame.

The seatbelt buckles for the second row seatbelts are attached to the seat frame.

THIRD ROW SEATBELTS

The retractor of each third row seatbelt is attached to the body on the D-pillar lower. The webbing runs from the retractor, through an exposed D-loop on the D-pillar, to an anchor point on the rear floor.

The buckles for the third row seatbelts are attached to the middle of third row seat frame.

SEATBELT RETRACTOR PRETENSIONERS

1. Retractor pretensioner - Front row outer
2. Retractor pretensioner - Front row center, second row outer, second row center and third row outer - 7 seat
3. Seatbelt pretensioner - NAS only
4. Retractor pretensioner - Second row bench central - 5 seat
5. Retractor pretensioner - Second row bench central - 7 seat

All of the seatbelt retractor pretensioners incorporate an emergency locking function and a load limiter function. On NAS vehicles, the retractors of the front passenger and rear seatbelts also incorporate an automatic locking function.

The emergency locking function locks the retractor when the seatbelt is pulled out of the retractor too quickly. The emergency locking function also locks when the vehicle is subjected to a sudden deceleration or severe tilt angle.

The automatic locking function allows the seatbelt to be tightened and locked, for the installation of a child seat.

LOAD LIMITER

On NAS vehicles, the retractor of the front passenger seatbelt incorporates an adaptive load limiter.

The load limiter has 2 different load limits:

• The standard load limit
• The lower load limit.

The lower load limit is designed to reduce the seatbelt chest loading on smaller seat occupants during an impact. The load limiter changes from the standard limit to the lower limit when the load limiter actuator is fired by the RCM.

The load limiter function progressively releases an amount of seatbelt when the belt tension exceeds a certain level.

The load limiter also limits the chest loading of an occupant during an impact.

SEATBELT BUCKLE

The buckle of each seatbelt incorporates a switch to provide a seatbelt status signal. The status signal is used for operation of the seatbelt reminder and beltminder systems, and for the firing strategy of the SRS.

The switches of the front row seatbelts (except front row seatbelt center) have signal and ground connections with the RCM. The switches of the rear seatbelts have connections to a vehicle ground point and to the BCM/ GWM. The RCM broadcasts on FlexRay and the BCM/ GWM broadcasts on High Speed (HS) Controller Area Network (CAN) body system bus.

SEATBELT WARNING INDICATOR

A seatbelt warning indicator is installed in and controlled by the IPC. The IPC receives seat buckle and first row occupancy information from the HS CAN Human Machine Interface (HMI) systems bus. The signals are transferred from the FlexRay and HS CAN body system bus through the BCM/ GWM.

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