Electronic Ignition

Models use a flywheel sensing permanent magnet generator to determine crankshaft position and engine speed.

On C70, S70 and V70, ECM computes correct timing of each ignition pulse in response to signals from RPM sensor, Camshaft Position (CMP) sensor, Mass Airflow (MAF) sensor, Engine Coolant Temperature (ECT) sensor, Throttle Position (TP) sensor, Knock Sensors (KS) and Transmission Control Module (TCM).

On S90 and V90, each cylinder is equipped with an individual ignition coil, eliminating the distributor. ECM computes when each ignition coil must deliver its voltage pulse. All 6 coils are controlled by 2 Ignition Discharge Modules (IDM).