Air Bag Systems: Service Precautions

SUPPLEMENTAL RESTRAINT SYSTEM

PRECAUTION

CAUTION:
- The LEXUS SC430 is equipped with a Supplemental Restraint System (SRS), which consists of a driver airbag, front passenger airbag and side airbag. Failure to carry out service procedures in the correct sequence could cause the SRS to unexpectedly deploy and possibly lead to serious injuries. Furthermore, if a mistake is made in servicing the SRS, it may fail to operate when required. Before performing servicing (including installation/removal, inspection and replacement of parts), be sure to read the following precautions.
- Before starting work, wait at least 90 seconds after the ignition switch is turned OFF and after the cable of the negative (-) battery terminal is disconnected.
(The SRS is equipped with a backup power source. If work is started within 90 seconds of turning the ignition switch OFF and disconnecting the cable from the negative (-) battery terminal,the SRS may deploy.)
- Do not expose the horn button assembly, front passenger airbag assembly, front seat airbag assembly, front seat airbag assembly (LH and RH), airbag sensor assembly center, airbag sensor front (LH and RH), side airbag sensor assembly (LH and RH) or door side airbag sensor (LH and RH) directly to hot air or flames.

NOTE:
- Malfunction symptoms of the SRS are difficult to confirm. DTCs are the most important source of information when troubleshooting. During troubleshooting, always confirm DTCs before disconnecting the cable from the negative (-) battery terminal.
- For minor collisions where the SRS does not deploy, always inspect the horn button assembly, front passenger airbag assembly, front seat airbag assembly, front seat airbag assembly (LH and RH), airbag sensor assembly center, airbag sensor front (LH and RH), side airbag sensor assembly (LH and RH) and door side airbag sensor (LH and RH).
- Before repair work, remove the airbag sensor if any kind of impact is likely to occur to the airbag sensor during the operation.
- Never use SRS parts from another vehicle. When replacing the parts, replace them with new ones.
- Never disassemble or attempt to repair the horn button assembly, front passenger airbag assembly, front seat airbag assembly, front seat airbag assembly (LH and RH), airbag sensor assembly center, airbag sensor front (LH and RH), side airbag sensor assembly (LH and RH) and door side airbag sensor (LH and RH) in order to reuse it.
- If the horn button assembly, front passenger airbag assembly, front seat airbag assembly, front seat airbag assembly (LH and RH), airbag sensor assembly center, airbag sensor front (LH and RH), side airbag sensor assembly (LH and RH) or door side airbag sensor (LH and RH) has been dropped, or if there are any cracks, dents or other defects in the case, bracket or connector, replace it with a new one.
- Use a voltmeter/ohmmeter with high impedance (10 kOhm/V minimum) for troubleshooting the electrical circuits.
- Information labels are attached to the periphery of the SRS components. Follow the cautions and instructions on the labels.
- After work on the SRS is completed, perform the SRS warning lamp check.
- When the cable is disconnected from the negative (-) battery terminal, the memory settings of each system will be cleared. Because of this, be sure to write down the settings before starting work. When work is finished, reset the settings of each system as it was before. Never use a backup power supply from outside the vehicle to avoid erasing the memory in any system.
- If the vehicle is equipped with a mobile communication system, refer to the applicable service precautions.




NOTE FOR INITIALIZATION:
When disconnecting the cable from the negative (-) battery terminal, initialize the mentioned systems after the cable is reconnected.