Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Ignition System: Description and Operation


System Schematic Diagram:






The Electronic Ignition System consists of a distributor, Ignition Control Module (ICM), Electronic Control Unit (ECU), and Crankshaft Position Sensor (CPS). Proper spark advance is fully automatic, and is provided by a load table built into the ECU. The ECU also monitors signals from the Coolant Temperature Sensor (CTS), engine rpm, Manifold Air Temperature (MAT) Sensor, and Manifold Absolute Pressure (MAP) Sensor when determining the correct ignition advance.