SRS System - Questions & Answers
NO. 76/11/94/USDATE: 04/15/94
MODEL
Range Rover Discovery
AFFECTED VEHICLES
All derivatives with factory fitted SRS system.
SUBJECT
Supplementary Restraint System (SRS)
Questions and Answers
This bulletin is designed to answer questions on the SRS system that may arise from Customers or Workshop Technicians. The general information provided below is additional to that provided in the appropriate workshop manual, section 76. When undertaking any repair work on the SRS system refer to the workshop manual.
Question: Are air bags standard on all vehicles?
Answer: Twin driver and passenger air bags are standard on both Discovery and Range Rover.
Question: Will the SRS system be activated by car phones?
Answer: No. This was an issue with the purely electronic systems, however the mechanical/electronic initiation system used by Land Rover is not susceptible to these types of "spurious" electrical signals.
Question: Will the SRS system deploy in a side impact?
Answer: The system is not designed to deploy during a side impact, only in a forward impact. However it will operate at up to 30 degrees either side of the longitudinal axis of the vehicle.
Question: Because Range Rover and Discovery are used on and off road, will the air bags deploy when used off road?
Answer: An extensive program of both on and off road testing has been undertaken by Land Rover to ensure that the correct functionality in all foreseeable situations has been fully proven.
Question: When should air bags be inspected?
Answer: The air bag SRS system does not require annual service. The only maintenance recommended is the replacement of the air bag modules after 10 years. The air bag SRS replacement date is shown in the owners service history record. The dealer should also be contacted if:
* An air bag inflates.
* The front of the vehicle is damaged even if the air bags do not inflate.
* Any part of the steering wheel cover or passenger module cover show signs of cracking or damage.
Question: What happens if the vehicle is hit when stationary?
Answer: Provided the ignition is on and it is a frontal impact (see also question 3) and the forces generated are high enough to activate the sensors the air bags will deploy. If the ignition is off, a different set of conditions apply, the system has been designed to be active while power is supplied via the ignition.
Question: Why should I want air bags when I have seat belts?
Answer: The air bags are a Supplementary Restraint System providing additional protection in severe life threatening frontal impacts only. They are not designed to replace seat belts. Seat belts must always be worn because:
* No protection is afforded against the effects of side impacts or rear impacts, roll-overs, or minor frontal impacts.
* Inflation and deflation take place very quickly and will not provide protection against secondary impacts.
Question: How quickly does the air bag deflate and will it hinder escape from the vehicle?
Answer: It takes 0.3 seconds from the time the sensors detect a severe impact to deployment of the bags - cushioning the head and torso - and deflation - its all over in a blink of the eye!
Question: If the vehicle has been in an accident which deploys the air bags but the vehicle is still driveable, should the vehicle be driven?
Answer: As the air bags will only deploy in life threatening situations it can be assumed that if the vehicle has been involved in an accident, there will be some form of vehicle damage which may prevent the vehicle being driven. As in all incidents driving the vehicle is dependent on the particular circumstances.
Question: When working on the vehicle, are there any precautions that can be taken to reduce inadvertent SRS lamp on conditions?
Answer: Before commencing any work on the SRS system components, always remove the ignition key from the starter switch and disconnect the battery.
Question: Are air bag system components serviceable or repairable?
Answer: There are no separately serviceable or repairable parts. For example, damaged or stripped threads on either the driver or passenger modules cannot be repaired, the modules need to be replaced.
Question: Are the fixings to secure the driver air bag to the steering wheel replaceable?
Answer: No. The fixings are encapsulated in the steering wheel and cannot be removed. If they are damaged, for example stripped threads, the steering wheel is required to be replaced.
Question: Are the special air bag system Torx head fixings reuseable other than those encapsulated in the steering wheel?
Answer: New fixing screws should always be used. However it should not normally be necessary to remove any air bag system components, except when replacing faulty components.