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Home >> Volvo >> 2002 >> V70 XC >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Alarm System, Control Modules, Engine Management Systems - Design And Function >> Alarm (2005-2007) >> Function >> Triggering the alarm
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Triggering the alarm

If the alarm is in active mode and the rear electronic module (REM) receives an indication from a directly connected sensor or the upper electronic module (UEM), a so-called alarm cycle will be initiated. The rear electronic module (REM) sends a siren activation command to the upper electronic module (UEM). At the same time, the rear electronic module (REM) sends a direction indicator lamp activation command to the central electronic module (CEM). The siren sounds for a period of approximately 25 seconds and then stops. The light signal will continue for an additional 4.5 minutes.

When the siren has stopped, the rear electronic module (REM) will carry out a check of the sensors that should be active in the vehicle. If the sensors are OK, the alarm will be reactivated. Should a fault occur in one of the sensors, it will be ignored by the rear electronic module (REM) during reactivation. Subsequently, the alarm can once again be triggered if required. The function for alarm re-triggering is market-dependent.