General Information

The Supplemental Restraint System (SRS) is designed to supplement the seat belt to help reduce the risk or severity of injury to the driver and front passenger by activating and deploying the driver, passenger, side airbags and seat belt pretensioners in certain frontal or side collisions. The SRS (airbag) consists of: the driver airbag module, located in the center of the steering wheel, which contains a folded airbag and inflator unit; the passenger airbag module, located in the instrument panel on the passenger side, which contains a folded airbag assembly with inflator; side airbag modules located in the front seats, which contain a folded airbag and inflator unit; curtain airbag modules located inside the headliner, which contain folded airbags and inflators. The SRSCM impact detection function is performed by an electronic accelerometer that continuously measures vehicle acceleration and sends a corresponding signal through amplification and filtering circuits to the microprocessor. The SRSCM (SRS Control Module) detects a frontal collision with the front impact sensor and a side collision with the side impact sensor, and determines airbag module deployment.

1. 1
   Self-diagnosis: The SRSCM constantly monitors the current operating state of the SRS and detects system malfunctions while the vehicle power is on. System malfunctions can be checked using trouble codes via GDS.
2. 2
   Airbag warning lamp illuminates: When a malfunction is detected, the module sends a signal to the airbag warning lamp located on the instrument panel. The airbag warning lamp indicates an SRS malfunction to the driver. When the ignition is turned on, the airbag warning lamp illuminates for approximately six seconds.
3. 3
   Diagnostic trouble code recording: When a malfunction occurs in the SRSCM system, the SRSCM stores the DTC corresponding to the malfunction. DTCs can be erased only by GDS. However, if an internal malfunction code is recorded or a reset failure is recorded, it must not be erased.
4. 4
   Self-diagnosis connector: Data stored in the SRSCM memory will be output to GDS or other external output devices through the connector located under the driver's side protective cover.
5. 5
   After the airbag has deployed, the SRSCM must not be reused and must be replaced.
6. 6
   The SRSCM detects whether the passenger has fastened the seat belt by a signal from the built-in switch in the seat belt buckle, and deploys the front passenger airbag at each specified collision speed.
7. 7
   Side airbag deployment is determined by the SRSCM, which detects the satellite sensor impact signal in a side collision, regardless of the seat belt condition.
8. 8
   The SRSCM detects vehicle rollover using a rollover sensor. SAB, CAB and BPT may deploy if the technician moves the SRSCM while the ignition is on. For this reason, disconnect the negative battery cable before performing any repair procedure on the SRSCM.
9. 9
   After the repair procedure, check that the SRSCM operates normally.