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Home >> Saab >> 2004 >> 9-3 Linear, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 50 (TRIONIC T8 Fuel Control System) >> Technical description >> Ionization Detection Module (740) >> Main task
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Main task

WARNING: This page is about a different car, the 2005 Saab 9-3. However, it is still accessible from the selected car via links, so may be relevant.

The CDM does an initial signal processing of the ionization signals from each ignition coil. The CDM transmits three signals to the ECM:

These signals are used for knock control, synchronization of ignition timing/fuel injection and for misfire detection.