Multiple Restraint System Control Unit. Restraint Control Module (RCM).
A sensor to determine the location on the vehicle of impact and the severity of the impact to determine if and which air bags should be deployed.

SENSOR

Fits XC60 (2009 - 2017)

Air Bag Crash Sensor
An airbag or SRS light can sometimes indicate a problem with the impact sensor on your Volvo XC60, particularly if it's been involved in a collision—at any speed. Have a technician inspect your vehicle's crash sensor.