| Diagnosis and Testing Principles of Operation WARNING:All safety belt assemblies, including retractors, buckles, front safety belt buckle support assemblies (slider bar), if equipped, child safety seat tether brackets and attaching hardware should be inspected after any collision. New safety belt assemblies should be fitted unless a qualified technician finds the assemblies show no damage and operate correctly. Failure to follow these instructions may result in personal injury. The safety belt system utilizes the conventional lap and diagonal three point fixing in both front seat positions and optional in the rear outboard seat positions. The front seat safety belt buckles are attached to the seat frame of each front seat. The rear seat safety belt buckles, if equipped, are mounted directly to the floor pan underneath the rear seat cushion. The front safety belt retractors, incorporate a torsion bar load limiting device. The device consists of a retractor reel which is mounted onto a spindle (torsion bar) which, once the sensor has locked the retractor reel and a predetermined load is applied, twists and pays out additional webbing into the system. The torsion bar load limiting device will only react if the safety belt is in use at the time of impact. Conventional safety belt retractors, if equipped, are fitted to both outboard rear seat positions. Emergency Locking Retractor (ELR) The retractors in all seat positions feature ELR. During normal operation the ELR allows free movement of the belted occupant. In an emergency the ELR will lock, preventing webbing payout and hence forward movement of the occupant. Locking may be achieved by one of two mechanisms: Vehicle Motion Sensor (VMS) The ELRs VMS is operated by sudden deceleration of the vehicle or excessive tilt. Once operated the VMS causes a locking pawl to be engaged, thus locking the retractor, preventing webbing payout. The locking method used is dependent on which type of ELR is fitted. When the vehicle is stationary, the VMS stabilizes, causing the pawl to disengage and unlock the retractor, allowing webbing payout. Webbing Motion Sensor (WMS) The ELRs WMS is operated by rapid acceleration of the webbing. Once operated, it causes a locking pawl to be engaged thus locking the retractor. Webbing payout is prevented in the same manner as VMS. Inspection and Verification - Verify the customer concern by operating the system.
- Visually inspect for obvious signs of mechanical and electrical damage.
Visual Inspection Chart | Mechanical | - Loose webbing
- Damaged/frayed webbing
- Safety belt retractor and tongue assembly
- Safety belt buckle
| - If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next stop.
- If the concern is not visually evident, verify the symptom and refer to the Symptom Chart.
Symptom Chart Symptom Chart | Symptom | Possible Sources | Action | | Normal mode - occupant restraint system inoperative | * Broken tooth on retractor sensor gear. * Loose webbing. | * REFER to the Functional Test in this section. | Safety Belt Testing Functional Test Poor Retraction If a safety belt does not retract correctly, check that the anchor covers and trim bezels are correctly installed and not rubbing against the safety belt webbing. Where necessary, check that the safety belt webbing is not rubbing at one end of the retractor cover slot and, if so, correct by loosening the retaining bolt, aligning the retractor to centralize the safety belt webbing and retighten the bolt. Both the vehicle motion sensor and the webbing motion sensor should be fully operational and can be checked by the following tests: Vehicle Motion Sensor Test Either of the following two procedures may be used to check correct operation of the vehicle motion sensor. Both methods require two technicians but note that technicians of larger than normal build should not be asked to conduct these tests. This is to avoid the possibility of a fully unrolled safety belt webbing being mistaken for a correctly locked safety belt retractor. Test Method 1 (braking) WARNING:It is important that during this test, the wearers allow the safety belts to provide the restraint and do not attempt to anticipate the sudden deceleration. The steering wheel should not be used as a brace. However, both driver and passenger should prepare themselves for the possibility that the safety belt will not lock. The passenger should hold their hands in front of them, just clear of the instrument panel or front seat backrest, depending on which safety belt is being tested. Failure to follow these instructions may result in personal injury. - Select for this test a quiet or private stretch of road. Make sure that the road is clear and that full visibility is maintained at all times.
- Both driver and passenger should adopt a normal, comfortable seating position. Both occupants should wear the safety belts and the safety belt webbing must be correctly adjusted, with no slack.
- Proceed at a speed of 10 km/h (6 mph). Do not exceed 10 km/h (6 mph) for this test.
- Apply the foot brake sharply to stop the vehicle. If the vehicle motion sensitive lock mechanism is operating correctly, the safety belt webbing will lock and restrain the wearer.
- Conduct the test twice in each front and rear passenger seat position.
- Any safety belt retractor which does not restrain the wearer during this test must not be reused. A new safety belt must be installed.
Test Method 2 (turning circle) This method requires a flat open area of private road, sufficient for the vehicle to be driven in a continuous circle on full steering lock. - The driver should wear the safety belt provided and the belt webbing must be correctly adjusted, with no slack.
- The passenger should occupy a rear seat with the safety belt correctly adjusted.
- Start the engine and, with the steering on full right-hand lock, drive the vehicle in a continuous circle at 16 km/h (10mph). Do not exceed 16 km/h (10 mph) for this test.
- When the speed is stable, the passenger should attempt to slowly extract the safety belt webbing from each safety belt retractor in turn. If the vehicle motion sensitive lock mechanism is operating correctly, it will not be possible to extract the webbing.
- Any safety belt retractor from which it is possible to extract the webbing during this test must not be used. A new safety belt must be installed.
Component Test With the vehicle stationary and on level ground take firm hold of the safety belt webbing (on the tongue side of the upper safety belt anchor) and pull out quickly. The retractor should lock within 0.25 meter (10 inches), preventing further webbing payout. Any safety belt retractor from which it is possible to extract further webbing must not be used. A new safety belt must be installed. | 
