Electronic Ignition System

WARNING: This page does not describe the selected car, but rather 15 other vehicles, including the 2003 Hummer H2, 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 GMC Sierra, and 2003 GMC Savana. However, it is still accessible from the selected car via links, so may be relevant.

The Electronic Ignition (EI) system is responsible for producing and controlling a high energy secondary spark. This spark is used to ignite the compressed air/fuel mixture at precisely the correct time. This provides optimal performance, fuel economy and control of exhaust emissions. This ignition system consists of a separate ignition coil connected to each spark plug by a short secondary wire. The driver modules within each coil assembly are commanded ON/OFF by the PCM. The PCM primarily uses engine speed and position information from the CKP and CMP sensors to control the sequence, dwell, and timing of the spark.

The EI system consists of Crankshaft Position (CKP) sensor, Camshaft Position (CMP) sensor, ignition coils, secondary ignition components and portion of the PCM.