Seat Belt Systems: Description and Operation
SAFETY BELT SYSTEMWARNING: All safety belt assemblies (including retractors, belt tension sensors [BTS] if equipped, buckles, shoulder belt height adjusters, [if so equipped], child safety seat tether attachments and attaching hardware) should be inspected after any collision. All new belt assemblies should be installed unless a qualified technician finds the assemblies show no damage and operate correctly. Belt assemblies not in use during a collision should also be inspected and new assemblies installed if either damage or incorrect operation is noted.
The automatic locking retractor (ALR) feature of the safety belt retractor must be checked by a qualified technician to verify that the ALR feature for a child seat is functioning correctly, in addition to the other checks for correct safety belt system function. A new belt and retractor assembly must be installed if the safety belt assembly automatic locking retractor feature or any other safety belt function is not operating correctly when inspected according to the functional inspection procedures. Failure to install a new belt and retractor assembly could increase the risk of injury in collisions.
The active restraint system consists of:
- the front safety belt retractors and tongues secured to the body behind the B-pillar trim panels.
- the driver and passenger safety belt buckle and pretensioners secured to the front seat assembly.
- the front center passenger safety belt and safety belt buckle ends (if equipped) secured to the floor pan on top of the front driver or passenger seat track.
- the rear outboard safety belt retractors secured to the body behind the quarter window trim panel.
- the rear center safety belt retractor and safety belt buckle assembly secured to the parcel shelf sheet metal under the parcel shelf trim panel and the floor pan under the rear seat cushion.
- the rear driver side and center passenger safety belt buckle assembly secured to the floor pan under the second row seat cushion.
A continuous-loop, single retractor active restraint system is used on all vehicles at all seating positions.
SAFETY BELT, LAP/SHOULDER
While the vehicle is in motion, the combination lap and shoulder belt adjusts to the occupant's movement However, if the vehicle brakes hard, corners hard or if the vehicle receives an impact of 8 km/h (5 mph) or more, the lap and shoulder belt locks and helps reduce the occupant's forward movement.
SAFETY BELT BUCKLE AND PRETENSIONER ASSEMBLY
The driver and passenger safety belt buckle and pretensioner are secured to the front seat assembly on the seat track. This allows the front safety belt buckle end to move with the front seat.
The safety belt buckle pretensioner is a pyrotechnic device that removes excess webbing from the safety belt system. The safety belt buckle pretensioner uses the same crash sensor system as the air bag supplemental restraint system (SRS). When the pretensioner deploys, the safety belt buckle moves downward, pulling excess webbing from the lap and shoulder safety belts
If the safety belt buckle pretensioner is deployed, a new assembly must be installed.
SAFETY BELT, LAP/SHOULDER-DUAL LOCKING MODE
The dual locking mode retractor on the shoulder belt portion of the combination lap/shoulder safety belt for the front outboard passenger, operates in 2 ways.
1. In the vehicle-sensitive (emergency locking) mode, the shoulder belt retractor will allow the occupant freedom of movement, locking tight only on hard braking, hard cornering or impacts of approximately 8 km/h (5 mph) or more. The front and rear outboard safety belt retractors can also be made to lock by pulling/jerking on the belt.
2. In the automatic locking mode, the shoulder belt retractor will be automatically locked and remain locked when the combination lap/shoulder safety belt is buckled and does not allow the occupant freedom of movement. This mode provides tight lap/shoulder belt fit on the occupant and on a child safety seat.
3. When the combination lap/shoulder belt is unbuckled and allowed to retract completely, the retractor will switch to the vehicle sensitive (emergency) locking mode.
The automatic locking mode must be used when installing a child safety seat in the front passenger and rear outboard seating positions.
SAFETY BELT TENSION SENSOR
The safety belt tension sensor:
- is a 3-wire Hall-effect sensor that is part of the front passenger safety belt and retractor assembly.
- is located at the safety belt anchor point.
- is used in conjunction with the occupant classification sensor (OCS) system.
The safety belt tension sensor is used by the OCS system to identify the presence of a child safety seat on the front passenger seat.
SAFETY BELT EXTENSION
A safety belt that is too short even when fully extended can be lengthened. The safety belt extension is available. This assembly will add approximately 20 cm (8 inches) to the length of the safety belt. Use the safety belt extension only if the safety belt is too short when fully extended. Do not use the safety belt extension to change the fit of the shoulder belt across the torso. Safety belt extensions are available at no cost from any authorized Ford or Lincoln-Mercury dealer.
CHILD SAFETY SEAT TETHER ANCHORS
WARNING: The child seat safety tether anchor/bolt MUST be securely tightened to specification. Otherwise, the child seat may not be correctly secured and the child could be injured if the vehicle is involved in a collision or stops suddenly.
Child safety seat tether anchors are attached to the package tray and are manufactured into the vehicle. See the appropriate removal and installation procedure.
Some manufacturers make child safety seats that include a tether strap that goes over the back of the vehicle seat and attaches to an anchoring point. Other manufacturers offer the tether strap as an accessory. Contact the manufacturer of the child safety seat for information about ordering a tether strap.
LOWER ANCHORS AND TETHERS FOR CHILDREN (LATCH)
The lower anchors and tethers for children (LATCH) system is a standardized and uniform attachment system for installing child safety seats in passenger vehicles. LATCH equipped child safety seats have 2 lower attachments that connect to the vehicle portion of the LATCH system.
The vehicle portion of the system consists of 2 attachment points (6 mm wires) bolted to the floor pan at all 3 second row seating positions. The attachment points protrude from the biteline between the seat cushion and seat backrest.
If a child safety seat was in use during a collision, inspect the vehicle portion of the system for damage. If any of the attachment points (6 mm wires) are damaged, a new one must be installed. See the appropriate removal and installation procedure.
SAFETY BELT WARNING SYSTEM
The safety belt warning indicator illuminates and a chime sounds to remind the occupants to fasten their safety belts.
The conditions of operation for the safety belt warning indicator and chime are as follows:
- If the driver or front passenger seat (if occupied) safety belt is not buckled before the ignition switch is turned to RUN, the safety belt warning indicator illuminates for 1-2 minutes and the warning chime sounds for 4-8 seconds.
- If the driver or front passenger seat (if occupied) safety belt is buckled while the warning indicator is illuminated and the reminder chime is sounding, then the safety belt warning indicator and reminder chime turn off.
- If the driver or front passenger (if occupied) safety belt is buckled before the ignition switch is turned to RUN, the safety belt warning indicator and reminder chime remain off.
BELT MINDER
The Belt Minder feature is a supplemental warning to the safety belt warning function. This feature provides additional reminders to the driver or passenger that the safety belt is unbuckled by intermittently sounding a chime and illuminating the safety belt warning lamp in the instrument cluster.
The passenger safety Belt Minder feature is activated only when the occupant classification sensor (OCS) system detects a passenger in the right front seat and the passenger weight exceeds a programmed limit.
To activate or deactivate the Belt Minder feature, refer to Instrument Panel, Gauges and Warning Indicators.