SAS CONTROL MODULE
id081000500200
Purpose
• The SAS control module controls the air bag system operation.
Function
• If the degree of impact exceeds the threshold during a frontal or frontal offset collision, the SAS control module operates (deploys) the following air bag modules.
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― Driver-side air bag module
― Passenger-side air bag module
― Driver/passenger-side pre-tensioner seat belt
• If the degree of impact exceeds the threshold during a lateral collision, the SAS control module operates (deploys) the following air bag modules.
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― Side air bag module on the collision side
― Curtain air bag module on the collision side
― Pre-tensioner seat belt on the collision side
• If an air bag is deployed due to a vehicle collision, the SAS control module sends an air bag deployment signal to each control module.
• When the signal is received, each control module performs the following controls to reduce secondary injuries caused by the vehicle collision.
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Backup power supply function
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• The backup power supply function enables the condenser to discharge and supply power to assure air bag system operation/deployment properly for a specified time even if the power supply to the SAS control module is cut due to a collision.
Configuration function
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• Identifies the variation of the air bag module installed to the vehicle when replacing the SAS control module with a new one.
• If the air bag module installed to the vehicle and the module identified by the SAS control module differ, a DTC is displayed.
• Refer to the Workshop Manual for the configuration setting procedure.
Yaw rate sensor
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• The yaw rate sensor in the SAS control module detects the vehicle yaw rate (vehicle turning angle speed), and sends the detected rate to the DSC HU/CM via special CAN lines between the SAS control module and the DSC CM.
Low-G sensor
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• The low-G sensor in the SAS control module detects the vehicle longitudinal accelerations, and sends the detected accelerations to the DSC HU/CM via special CAN lines between the SAS control module and the DSC CM.
Construction
• SAS control module installed under the rear console.
• The following sensors are built into the SAS control module.
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― Crash sensor
― Yaw rate sensor
― Low-G sensor
• If the degree of impact detected by the crash zone sensor and the crash sensor built into the SAS control module exceeds the set value during a frontal collision to the vehicle, the SAS control module sends an operation (deployment) signal to the air bag module and the pre-tensioner seat belts.
• If the degree of impact detected by side air bag sensor No. 1 or No. 2 and the crash sensor built into the SAS control module exceeds the set value during a side collision to the vehicle, the SAS control module sends an operation (deployment) signal to the side air bag module and curtain air bag module.
Operation
Deployment during frontal or frontal offset collision
1. During a frontal or frontal offset collision, the crash zone sensor and the crash sensor built into the SAS control module detect an impact.
2. Each crash sensor converts the detected impact to an electrical signal and outputs it to the SAS control module.
3. The SAS control module calculates the degree of impact at the judgement and safing circuit based on the electrical signal input from each crash sensor.
4. If the calculated degree of impact exceeds the threshold, the SAS control module completes an ignition circuit at the output control circuit and sends an operation (deployment) signal to the driver/passenger-side air bag module, pre-tensioner seat belt, and lap pre-tensioner seat belt.
Deployment during lateral collision
1. During a side-impact collision, side air bag sensors No.1 and 2, and the crash sensor built into the SAS control module detect an impact.
2. Each crash sensor converts the detected impact to an electrical signal and outputs it to the SAS control module.
3. The SAS control module calculates the degree of impact at the judgement and safing circuit based on the electrical signal input from each crash sensor.
4. If the calculated degree of impact exceeds the threshold, the SAS control module completes an ignition circuit at the output control circuit and sends an operation (deployment) signal to the side air bag module, curtain air bag module, and pre-tensioner seat belt.
DSC system control
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• The vehicle angle speed and accelerations detected by the yaw rate and low-G sensors in the SAS control module are sent to the DSC HU/CM via special CAN lines.
• The DSC system controls based on the signal sent from the SAS control module. For the DSC system operation, refer to the
DSC HU/CM.
Passenger air bag deactivation (pad) switch operation (deployment) control
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• When the PAD switch is turned to the OFF position, the SAS control module inhibits operation (deployment) of the passenger-side air bag module, passenger-side side air bag module, and the passenger-side pre-tensioner seat belt even if the degree of impact from a collision is sufficient for normal air bag module operation (deployment). At the same time, the PAD indicator illuminates to alert the driver and passengers (passenger-side seat) of the inoperational (undeployable) condition of the air bag.
• When the PAD switch turned to the ON position, the passenger-side air bag module, passenger-side side air bag module, and the passenger-side pre-tensioner seat belt operate (deploy) normally during a collision and the PAD indicator goes out.
• When the ignition switch is turned to the ON position, the PAD indicator illuminates for approx. 6 s while the SAS control module inspects for malfunctions in the circuit. If a malfunction is detected in the circuit, a DTC is displayed.
Fail-safe
• If the SAS control module performance/function cannot be maintained due to any cause, the fail-safe function stops air bag system control and flashes the air bag system warning light to prevent the air bags from operating (deploying) accidentally.
