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The supplemental inflatable restraint (SIR) system supplements the protection
offered by the occupant seat belt system. The SIR system has several inflator
modules located throughout the vehicle, i.e. The inflatable restraint steering wheel
module, inflatable restraint IP module in passenger side of dash, and the inflatable
restraint side impact module - LF and RT. Each inflator module has a deployment
loop that is controlled by the inflatable restraint Sensing and Diagnostic Module
(SDM), which is mounted inside of the vehicle. The SDM determines the severity of a
collision with the assistance of various sensor inputs. When the SDM detects a
collision of sufficient force, it will process the information provided by the sensors to
further support inflator module deployment. The SDM performs continuous
diagnostic monitoring of the SIR system electrical components. Upon detection of a
circuit malfunction, the SDM will set a diagnostic trouble code (DTC) and inform the
driver by commanding the instrument panel cluster (IPC) to turn the AIR BAG
indicator ON. The steering column and knee bolsters are designed to absorb energy
and compress during frontal collisions in order to limit leg movement and decrease
the chance of injury to the driver and front passenger.
A frontal collision of sufficient force will deploy the frontal inflator modules. The SDM
contains a sensing device (accelerometer) that converts vehicle velocity changes to
an electrical signal. In some vehicles, the SDM receives a signal from the electronic
frontal sensor (EFS) which can help determine the severity of some types of frontal
collisions. The SDM contains a microprocessor, which performs calculations using
the measured accelerations and compares these calculations to a value stored in
memory. When the generated calculations exceed the stored value, the SDM will
cause current to flow through the frontal deployment loops, deploying the frontal
inflator modules. Once the inflator modules are inflated, they quickly deflate through
the air bag vent holes and/or the bag fabric. After the inflator modules are deployed,
the SDM sets a deployment commanded DTC and then commands the IPC to turn
the AIR BAG indicator ON. The SDM, IP module, steering wheel module, steering
wheel module coil and the connecting wires make up the frontal deployment loops.
The SDM continuously monitors the deployment loops for malfunctions and
commands the IPC to turn the AIR BAG indicator ON if a fault is detected.
offered by the occupant seat belt system. The SIR system has several inflator
modules located throughout the vehicle, i.e. The inflatable restraint steering wheel
module, inflatable restraint IP module in passenger side of dash, and the inflatable
restraint side impact module - LF and RT. Each inflator module has a deployment
loop that is controlled by the inflatable restraint Sensing and Diagnostic Module
(SDM), which is mounted inside of the vehicle. The SDM determines the severity of a
collision with the assistance of various sensor inputs. When the SDM detects a
collision of sufficient force, it will process the information provided by the sensors to
further support inflator module deployment. The SDM performs continuous
diagnostic monitoring of the SIR system electrical components. Upon detection of a
circuit malfunction, the SDM will set a diagnostic trouble code (DTC) and inform the
driver by commanding the instrument panel cluster (IPC) to turn the AIR BAG
indicator ON. The steering column and knee bolsters are designed to absorb energy
and compress during frontal collisions in order to limit leg movement and decrease
the chance of injury to the driver and front passenger.
A frontal collision of sufficient force will deploy the frontal inflator modules. The SDM
contains a sensing device (accelerometer) that converts vehicle velocity changes to
an electrical signal. In some vehicles, the SDM receives a signal from the electronic
frontal sensor (EFS) which can help determine the severity of some types of frontal
collisions. The SDM contains a microprocessor, which performs calculations using
the measured accelerations and compares these calculations to a value stored in
memory. When the generated calculations exceed the stored value, the SDM will
cause current to flow through the frontal deployment loops, deploying the frontal
inflator modules. Once the inflator modules are inflated, they quickly deflate through
the air bag vent holes and/or the bag fabric. After the inflator modules are deployed,
the SDM sets a deployment commanded DTC and then commands the IPC to turn
the AIR BAG indicator ON. The SDM, IP module, steering wheel module, steering
wheel module coil and the connecting wires make up the frontal deployment loops.
The SDM continuously monitors the deployment loops for malfunctions and
commands the IPC to turn the AIR BAG indicator ON if a fault is detected.
Airbag (SIR) Description and Operation
WARNING LIGHTS
