Supplemental Restraint System (SRS) activates air bag module and seat belt pre-tensioner when it detects a frontal collision or a side collision or rollover that is more than the specified limit. Together with other safety devices, it reduces the impact that occupant receives when vehicle collision occurs.

Air bag diagnosis sensor unit supplies power supply to air bag module and pre-tensioner seat belt when deceleration that is more than the specified limit is detected by G sensor in air bag diagnosis sensor unit, crash zone sensor, or satellite sensor. Air bag module is composed of electric igniter (squib), filter, pyrotechnic material, and gas generating material. When air bag module receives a signal from air bag diagnosis sensor unit, air bag module ignites pyrotechnic material using electric igniter (squib) so that gas generating material generates high temperature nitrogen gas. The gas through filter activates air bag. At the same time, pre-tensioner seat belt receives power supply from air bag diagnosis sensor unit, gas generator is activated, and then gas is generated. Balls in pipe are moved according to generated gas pressure and strike pinion gear on ELR shaft. ELR shaft rotates and retracts seat belt.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

System Description: Notes

Use the Manual With the Right Hardware

When to See a Mechanic