Air Bag and Supplementary Restraint System (SRS) Precautions

General Precautions

The supplementary restraint system (SRS) includes air bags, pre-tensioners, and other safety-related components. The SRS contains components which could be potentially hazardous to the technician if not serviced and handled correctly.

Warning: Always follow these precautions and the relevant Service Manual procedures when servicing air bags and other SRS components. Only trained professionals should service the SRS.
Warning: An undeployed air bag module or pre-tensioner contains sodium azide, which is poisonous and extremely flammable. Contact with water, acid or heavy metals might produce harmful or explosive compounds. Do not dismantle, incinerate or bring into contact with electricity, before the unit has been deployed.
Warning: In the event of an air bag or seat belt tensioner deployment, certain air bag and seat belt components must be replaced, and other components must be inspected for damage. Refer to body repair tech note BR-14-20-001 for a specific list of items that must be inspected and replaced.
Warning: Do not expose an air bag module or seat belt pre-tensioner to heat exceeding 85°C.

These precautions are not restricted to operations performed when servicing the SRS; the same care must be exercised when working on other systems and components located near the SRS components:

Making the system safe

Before working on, or in the vicinity of, SRS components, perform the following procedures to disable the system:

  1. Use Toolbox to check for any stored fault codes.
  2. Perform the vehicle electrical isolation procedure (refer to procedure).
  3. Wait 1 minute for the energy reserve capacitors to discharge.

Installation

Carefully inspect SRS components before installation. Do not install a component if it shows evidence of being dropped or improperly handled, such as dents, cracks or deformation.

Warning:
  • Never install used SRS components from another vehicle or attempt to repair an SRS component. Use only new, genuine Tesla replacement parts.
  • Never use SRS components that lack clear identification labels.
  • Never use a PSRCM that has been dropped.
  • Never apply electrical power to an SRS component unless instructed to do so as part of an approved test procedure.
  • Always use new fasteners when replacing SRS components. Ensure that the fasteners are tightened to the specified torque.
  • Ensure SRS components are not contaminated with oil, grease, detergent or water.
  • Ensure the Passive Safety Restraint Control Module (PSRCM) is installed correctly. There must not be any gap between the PSRCM and its mounting bracket. An incorrectly mounted PSRCM might cause the system to malfunction.
  • Do not supply power to the PSRCM until all other SRS components are connected.
Note: After seat belt pre-tensioner deployment, the affected seat belts will be locked and can not be used as conventional seat belts. They must be replaced.

SRS component testing precautions

The air bags and other SRS components are triggered using relatively low operating currents. To prevent accidental deployment, always adhere to the following precautions:

Warning: Do not use a multi meter or other general purpose test equipment on SRS components. Only use the recommended diagnostic equipment to diagnose system faults.
Warning: Do not use electrical test equipment on any SRS harness unless all SRS components are disconnected.

Handling and storage

Warning:
  • The PSRCM, pre-tensioners, and air bags must be stored in a secure steel cabinet at room temperature. The storage area must comply with all legal requirements. It must be away from flammable items and have suitable fire extinguishers or other fire extinguishing equipment. Ensure that heat, fire, water and corrosive substances cannot contaminate the stored components.
  • Keep new SRS components in the original packaging until they are ready to be installed.
  • Never wrap your arms around an air bag module. If an air bag module has to be carried, hold it by the cover, with the cover face up and the base away from your body.
  • When handling seat belt pre-tensioners with retracting spool assemblies, never point the end of the piston tube towards your body or at other people. Hold with the piston pointing towards the ground. Do not grip by the retractor reel or seat belt. Hold the outer casing only.
  • Always keep components cool, dry and free from contamination.
  • Never transport air bag modules or seat belt pre-tensioners in the cabin of a vehicle.
  • Never attach anything to an air bag cover or any trim component covering an air bag module. Do not allow anything to rest on top of an air bag module.
  • Do not apply grease or cleaning solvents to seat belt pre-tensioner units. Component failure could result.
  • Never drop an air bag or SRS component. The PSRCM is a particularly shock sensitive device and must be handled with extreme care.
Warning: Store the air bag module with the deployment side facing up. This will prevent it from being propelled if accidentally deployed, which might cause injury.
Warning: Improper handling or storage can internally damage air bag modules and pre-tensioners, making them inoperative. If you suspect a module has been damaged, install a new component and refer to the Deployment/Disposal Procedures for disposal of the damaged module.

SRS Harnesses and Connectors

Note: SRS wiring can be identified by a special yellow outer sleeve protecting the wires (black with yellow stripe protective coverings are sometimes used).
Warning: Never attempt to modify, splice or repair SRS wiring.
Warning: Never install electronic equipment (such as a mobile telephone, two-way radio or in-car entertainment system) in such a way that it could generate electrical interference in the SRS harnesses. Seek specialist advice when installing such equipment.
Warning: Always ensure that SRS wiring is routed correctly. Be careful to avoid trapping or pinching the cables. Do not leave the connectors hanging loose or allow SRS components to hang from their harnesses. Look for possible points of chafing.

Steering Angle Sensor (SAS) Precautions

Caution: Always follow the procedure for fitting and checking the SAS as instructed in the air bag and SRS repairs section. Comply with all safety and installation procedures to ensure the system functions correctly.
Caution: Observe the following precautions:
  • Do not unlock and rotate the SAS when it is removed from the vehicle.
  • Always ensure the SAS is removed and installed in its centered position and with the front road wheels in the straight ahead position. Refer to the air bag and SRS repair section for the correct removal and installation procedure.
  • If a new SAS is being installed, ensure the locking tab holding the SAS rotational position is not broken; units with a broken locking tab should not be used.

Warning Labels

Warning: Read and follow all warnings and cautions printed on SRS component warning labels.

SRS Component Deployment

If a vehicle is to be scrapped and contains an undeployed air bag module or pre-tensioner, the module must be manually deployed.

Always observe the following precautions:

Warning: Only personnel who have undergone the appropriate training should undertake deployment of air bag and seat belt pre-tensioner modules.
Warning: A recently deployed air bag or seat belt pre-tensioner is very hot. DO NOT handle a deployed module until at least 30 minutes after deployment.
Warning: Only use approved deployment equipment, and only deploy air bags and pre-tensioner components in a well-ventilated designated area. Ensure components are not damaged or ruptured before deployment.
Warning: Do not lean over air bag modules or seat belt pre-tensioner units when connecting deployment equipment.
Warning: Contact with chemicals from deployed and damaged SRS components could present a health hazard. Wear protective clothing when handling and seal deployed units in a plastic bag. DO NOT eat, drink or smoke when handling SRS components.
Warning: Deployment of air bag modules and seat belt pre-tensioners can cause injury to personnel in the close vicinity of the deploying unit. Ensure that all personnel are at least 15 m (50 ft) away from the deployment zone. Possible sources of injury include:
  • Impact - due to inflating air bag or pre-tensioner operation causing component 'kick'.
  • Hearing - due to noise produced by deploying air bags and seat belt pre-tensioner units.
  • Burns - hot component parts and gases.
  • Irritation to eyes and lungs - from deploying gases or combustion residue.
Warning: Ensure the SRS component to be deployed is securely fastened to its mounting.
Warning:
  • Only use deployment equipment approved for the intended purpose.
  • Test the deployment tool before beginning the deployment procedure.
  • Notify the relevant authorities of intention to deploy SRS components.