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System Overview: Signals

The table below summarizes the input signals to and output signals from the upper electronic module (UEM). The signal types are divided into directly connected signals, serial communication and controller area network (CAN) communication. The illustration below displays the same information with the Volvo component designations.

Input signals Output signals
Directly connected:  Directly connected: 
(power supply unless otherwise stated)
  • Control signal reading lamps (x 4 XC90 x 5)
  • Remote control (data)
  • Remote control (frequency)
  • Remote control (signal strength)
  • Photo sensor rear view mirror (x 2).
  • Mass movement sensor module (MMS) (7/122) (optional extra) and (7/158), or ultrasonic sensor module (IMS) (7/199) (optional extra). (XC90 has MMS (2 x) for MY -2011 which is replaced by IMS (1 x) for MY 2012-)
  • Reading lamps (x 4, XC90 x 6)
  • Roof lighting
  • Cargo compartment lighting
  • Voltage supply signal EXT. X
  • Remote control receiver
  • Anti-dazzle in the rear view mirror (optional extra)
  • Diodes in the rear view mirror.
Via serial communication:  Via serial communication: 
  • Siren (SCM) (16/35) (extra equipment) (withdrawn on XC90 from and including structure week 201128)
  • Sun roof module (SRM) (4/33) (optional extra)
  • Mass movement sensor module (MMS) (7/122) (optional extra) and (7/158) (for XC90 MY -2011), or ultrasonic sensor module (IMS) (7/199) (for XC90 MY 2012-)
  • Rain sensor module (RSM) (7/149) (optional extra).
  • Siren (SCM) (16/35) (extra equipment) (withdrawn on XC90 from and including structure week 201128)
  • Sun roof module (SRM) (4/33) (optional extra)
  • Mass movement sensor module (MMS) (7/122) (optional extra) and (7/158) (for XC90 MY -2011), or ultrasonic sensor module (IMS) (7/199) (for XC90 MY 2012-)
  • Rain sensor module (RSM) (7/149) (optional extra).
Via Controller Area Network (CAN) communication:  Via Controller Area Network (CAN) communication: 
  • Central electronic module (CEM) (4/56)
  • Driver door module (DDM) (3/126)
  • Engine control module (ECM) (4/46)
  • Phone module (PHM) (16/60) (optional equipment).
  • Supplemental restraint system module (SRS) (4/9).
  • Accessory electronic module (AEM) (4/78) (optional equipment)
  • Central electronic module (CEM) (4/56)
  • Driver door module (DDM) (3/126)
  • Passenger door module (PDM) (3/127)
  • Phone module (PHM) (16/60) (optional equipment).
  • Rear electronic module (REM) (4/58).
Fig 1: Identifying Volvo Component Designations.
GLL180380Courtesy of VOLVO CARS CORPORATION