FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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System Overview






System overview

Control module




The supplemental restraint system module (SRS) handles functions for:
- seat belt tensioners
- side impact sensors
- front impact sensor (certain markets and models only)
- seat position sensors (XC90 USA/CDN only)
- side impact protection (SIPS) bags
- front driver and passenger airbags
- inflatable curtains
- SRS indication
- passenger airbag indication
- collision output signal
- collision registration
- adaptive steering column (XC90 USA/CDN only)
- front seat belt buckles
- switch on/off, front passenger airbag (not USA/CDN)
- occupant weight sensor (OWS) (certain markets and models only)
The control module is in the transmission tunnel, between the gear selector lever and the parking brake.
The supplemental restraint system module (SRS) communicates with directly connected components and with other control modules via the Controller Area Network (CAN).
The control module checks the input and output signals through an integrated diagnostic system. A diagnostic trouble code (DTC) is stored if the control module detects a fault.
Any diagnostic trouble codes (DTCs) are stored in the control module memory. The data can be read off using VIDA.
The control module can process multiple collisions, frontal collisions, collisions from behind, side-on collisions and overturning.
The control module function can be easily checked by switching on the ignition. The SRS indicator lamp in the combined instrument panel must light up when the key is in ignition positions I-III. The lamp goes out after a short while if no faults are detected. This means that the supplemental restraint system (SRS) is functioning correctly.
For further information, also see Signal specifications.

Signals
The table below summarizes the input signals to and output signals from the supplemental restraint system module (SRS). The signal types are divided into directly connected signals, LIN and CAN communication. The illustration below displays the same information with the Volvo component designations.