System Overview: Notes

2009 Volvo XC70 BaseSECTION Notes
Fig 1: Locating Start Inhibition System Related Modules
GLL173555Courtesy of VOLVO CARS CORPORATION

The start inhibition system is a comprehensive function of the vehicle security system. The logic for start inhibition is in the engine control module (ECM). The system for start inhibition reads off a number of values from the controller area network (CAN). These values are used to determine whether the criteria for the engine control module (ECM) to activate the starter motor are met. The system for start inhibition reads off whether the immobilizer check is OK or not.

There are a number of functions in the car's security system:

  • Immobilizer
  • Steering column lock
  • Key warning
  • Alcolock (option)
  • Remote-controlled immobilization (option, only certain markets).

The various functions depend on different control modules and components.

The following are included in the immobilizer system:Β 

  • Central electronic module (CEM)
  • Keyless vehicle module (KVM) (only vehicles with the keyless locking system)
  • Ignition antenna unit (IAU)
  • Engine control module (ECM)
  • Brake control module (BCM)
  • Phone module (PHM) (only vehicles with remote-controlled immobilization).

The following are included in the steering column lock system:Β 

  • Central electronic module (CEM)
  • Engine control module (ECM)
  • Brake control module (BCM)
  • Transmission control module (TCM)

The following are included in the key warning system:Β 

  • Central electronic module (CEM)
  • Driver information module (DIM)
  • Keyless vehicle module (KVM) (only vehicles with the keyless locking system)

Included in the alcolock system (not in vehicles with the keyless entry locking system):Β 

  • Central electronic module (CEM)
  • Driver information module (DIM)
  • Remote Receiver Module (RRX)

Definitions:Β 

Activated system:Β  The system means that the vehicle cannot be started.

Deactivated system:Β  Key check has been carried out and the remote key has been approved. The system permits the car to start.

RENDER: 1.0x

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