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Home >> Volvo >> 2002 >> S80 Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 35 (Control Modules - Design And Function - 2 Of 4) >> Immobilizer (2005-2009) >> Design >> Engine Control Module (ECM)
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Engine Control Module (ECM)

WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2009 Volvo S60, 2008 Volvo S60, 2007 Volvo S60, 2006 Volvo S60, and 2005 Volvo S60. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Engine Control Module
GLL142321Courtesy of VOLVO CARS OF NORTH AMERICA.

The engine control module (ECM) (4/46) controls the ignition system in the vehicle and controls activation of the starter motor via the starter motor relay (applicable to B8444S only). The engine control module (ECM) also grants permission to the central electronic module (CEM), indicating whether the fuel pump is permitted to run when ignition is attempted. These functions are activated once an approved check of the ignition key has been carried out and an identity check has been carried out between the engine control module (ECM) and the central electronic module (CEM) and the result approved.

In order for the engine control module (ECM) to work in the immobilizer system, the control module must be programmed with codes. This takes place for the first time during assembly in the factory, and subsequently takes place in the event the control module is replaced (when downloading software).

For further information, see Design and Function, engine control module (ECM).