System Overview

System overview

Control module





The supplemental restraint system module (SRS) handles functions for:
- belt tensioners
- side impact sensors
- front impact sensor (not XC60)
- seatbelt retractor sensor (only XC60 or USA/CAN)
- seat position sensor (USA/CAN only)
- adaptive seatbelt force limiter (only XC60 or USA/CAN)
- side airbags
- front airbags
- inflatable curtains
- SRS indication
- passenger airbag indication
- collision output signal
- collision registration
- adaptive steering column (USA/CAN only)
- front belt buckle detection
- rear belt buckle detection (certain markets only)
- internal CAN network, supplemental restraint system module (SRS)
- occupant weight sensor (OWS) (USA/CAN only)
- switch, front passenger airbag (not USA/CAN)
- roll-over sensor (only XC60)
The control module is located under the cup holder in the tunnel console.
The supplemental restraint system module (SRS) communicates on the CAN network with both directly connected components and other control modules. In certain markets, the control module can also communicate with components via an internal CAN network.
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 are stored in the control module memory. The data can be read off using the diagnostic tool.
The control module can handle frontal collisions, side collisions, collisions from behind, and roll-overs (only XC60).
A simple way to check that the SRS system is functional is to switch the ignition to position II. The SRS warning lamp in the driver information module should light when the ignition is switched to position II. If no faults are detected, the warning lamp goes out after a short delay. This means that the SRS system is fully functional and fault-free.
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 and CAN communication. The illustration below displays the same information with the Volvo component designations.