Seat Belt Systems: Description and Operation
DESCRIPTIONThe passive restraint system is similar in design to the type fitted to the XJS. The passive belt is a single diagonal belt, fed from an inertia reel assembly mounted on the seat slide (centre console side) to a motorized runner slotted in a guide rail, attached to the cantrail. A quick release buckle for emergency use is located at the cantrail end of the belt.
An independent second belt (inertia reel lap type) to be used in conjunction with the passive belt is fitted, and must be manually secured by the occupant.
The Passive belt is driven by a motor and winch assembly mounted in the BC post - one to the LH side and one to the RH side of the vehicle. The system is controlled by an ECU mounted above the driver's side dash liner.
The seat belt warning on the VCM and a separate warning light located on the fascia below the hazard warning switch indicate that the driver's passive belt is not located in the restraining position. Also in operation is a six second audible warning.
OPERATION
The system is actuated when the doors are closed and the ignition is turned to position II. Both seat belt warning lights will remain illuminated until the driver's passive (automatic) belt is located in the restraining position; the audible warning, once started, will continue for six seconds.
Both driver and passenger belt should operate simultaneously even when the passenger seat is unoccupied. This will ensure that the passenger door mirror is not obscured by the belt.
The passive belt deploys automatically to the unrestraining position when the ignition key is turned to position I or OFF, or when the adjacent door is opened. However, with reverse gear selected, should the driver's door be opened (to aid driver vision) the belt is prevented from travelling to the unrestraining position, thereby avoiding the possibility of entangling the leaning driver.
A further safety feature of the system is its connection with the inertia switch. If the inertia switch is tripped with the ignition ON, no movement of the passive belt will occur. In addition, the doors will be unlocked.
To prevent the occupant from being trapped in the vehicle in the event of a road accident, the buckle at the shoulder end of the belt can be released by operating the red button marked 'PRESS'.
WARNING: IF THE BELT IS RELEASED FOR ANY REASON, IT MUST BE RECONNECTED BEFORE THE VEHICLE IS DRIVEN AGAIN.
In the unlikely event of a malfunction of the deployment system, two emergency tongues with protective covers are stored in the glovebox to allow temporary use of the vehicle.
The tongues are right and left handed and marked RH TOP and LH TOP respectively. Insert the correct tongue into the trim finisher channel on the B post, sliding it down until it engages with the assembly anchorage at the end of the runner rail. Release the diagonal seat belt buckle from the runner/tongue assembly by operating the red 'PRESS' button, and manually attach the buckle to the emergency tongue. Fit the protective cover to the exposed runner/tongue assembly.
Due to the sensitivity of the belt inertia reels, rapid or jerky seat adjustment may cause them to lock, preventing the system from deploying completely. It is preferable to adjust the seat after the belt has deployed to the restraining position. If the inertia reel mechanism is locked, slowly adjust the seat forwards and ease the belt from the inertia reel or use the emergency release. Ensure the belt is re-connected before the vehicle is driven. Labels refering to the above are attached to the sunvisor and belt webbing.
OPTIONS FOR USE ON EARLY VEHICLES
Incorporation of the passive restraint system necessitates modification at the body-in-white stage of construction.
Fitment of the passive restraint system will not be possible therefore, to vehicles manufactured before 1st June 1988. Additionally the front seat slides have been made narrower to accommodate the passive restraint reels, and consequently seat slides are not interchangeable with the preceding type.