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Home >> Volvo >> 2012 >> XC90 Base, FWD >> Repair and Diagnosis >> Engine Performance >> System >> Electronic Modules - Design And Function >> Differential Electronic Module (DEM) (TF-80SC AWD; 2005-2008) >> System Overview >> Signals
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System Overview: Signals

The table below summarizes input and output signals to and from the Differential Electronic Module (DEM). The illustration below displays the same information with the Volvo component designations.

Input signals Output signals
Directly connected:  Directly connected:  (supply voltage unless otherwise specified)
  • Oil pressure and temperature sensor 
  • Electrical feed pump 
  • Axial solenoid  - pulse width modulated (PWM) signal
Via Controller Area Network (CAN) communication:  Via Controller Area Network (CAN) communication: 
  • Central Electronic Module (CEM)  (4/56), informs on the position of the ignition key and reverse gear status amongst other things.
  • Brake Control Module (BCM)  (4/16), informs on the speed of the wheels from the wheel speed sensors and ABS modulation status amongst other things.
  • Driver Information Module (DIM)  (5/1), informs on parking brake switch status.
  • Engine Control Module (ECM)  (4/46), informs on engine speed, driver engine torque request, calculated engine torque, accelerator pedal position, stop lamp switch status and clutch pedal switch status, amongst other things.
  • Brake Control Module (BCM)  (4/16), receives information on clutch unit status and torque transferred to the rear axle.
  • Central Electronic Module (CEM)  (4/56), receives information on the diagnostic status of the Differential Electronic Module (DEM).
Fig 1: Differential Electronic Module (DEM) Network
GLL149369Courtesy of VOLVO CARS CORPORATION