Electronic control unit installed under the floor tunnel lining
The ECU has built-in micromechanical sensors that measure the longitudinal and lateral acceleration of the car in a collision
The ECU evaluates the impact force by comparing the values it receives from the front impact sensor, side impact sensors, and internal electronic sensors with a predetermined value.
If the deceleration signal due to a frontal or side impact exceeds a predetermined value, the computer will trigger the pretensioners and deploy the corresponding airbags.
If the vehicle's battery ruptured during the crash, the voltage holding circuit in the ECU would still be able to activate the airbags for some time after the impact;
– frontal and side impact sensors that transmit acceleration information to the system control unit
The force and direction of impact in a traffic accident is determined by the electronic control unit of the passive safety system using impact sensors. Based on the signals from the sensors, the control unit activates the airbags and front seat belt pretensioners.
Front impact sensors are located on the side members of the car body behind the front bumper
Side impact sensors are mounted on the B-pillar on the inside behind the pillar trims;
Side impact sensors are installed on cars with side airbags and inflatable curtains in the variant.
Replacing the electronic control unit for the security system
Disconnect the wire from the negative terminal of the battery
Removing the floor tunnel lining, described in the article - How to remove Hyundai Solaris floor tunnel lining
We fold back the fixing bracket and disconnect the wire blocks of the passive safety control unit
We unscrew the three bolts securing the security control unit to the body
And remove the block
When installing the block, pay attention to the arrow on the label.
The arrow must point in the direction of the vehicle
Install the safety block and all parts in reverse order
Replacing shock sensors
Disconnect the negative battery terminal
Wait at least one minute to discharge the capacitors of the airbag deployment system
Remove the lower part of the lining of the central pillar
Press the retainer of the side impact sensor wire block
Disconnect the block from the sensor
We unscrew the bolt securing the sensor to the central pillar of the body and remove the sensor
We install the sensor and others did it in reverse order
Replacing the front impact sensor
Disconnect the negative battery terminal
Wait at least one minute to discharge the capacitors of the airbag deployment system
Remove the front fender liner
We shift and squeeze the retainer for fastening the front impact sensor wire block
Disconnect the block from the sensor
Unscrew the front impact sensor mounting bolt
Remove the sensor
Install the front impact sensor and other parts in reverse order.