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Home >> Volvo >> 2012 >> XC90 Base, FWD >> Repair and Diagnosis >> Engine Performance >> System >> Electronic Modules - Design And Function >> Engine Control Module (ECM) (B8444S; 2005-2011) >> Function >> Controlling The Generator
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Controlling The Generator

Fig 1: Identifying ACM, ECM & CEM Communication Link
GLL150024Courtesy of VOLVO CARS CORPORATION

The engine control module (ECM) (4/46) regulates the charge voltage of the generator (GEN) (6/26) (via LIN communication) when requested by the central electronic module (CEM) (4/46) (via CAN communication).

The engine control module (ECM) can change the charge voltage requested by the central electronic module (CEM). to suit certain operating conditions such as engine start, idle speed or high engine load.

The value of requested charge voltage from the engine control module (ECM) and the charge current of the generator can be read off.

The alternator control module (ACM) (6/26) transmits information to the engine control module (ECM) regarding any faults). The diagnostic trouble codes (DTCs) are stored in the engine control module (ECM) in the event of a fault. In the event of certain faults, information about these faults is also transmitted to the central electronic module (CEM).