LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Cadillac >> 2003 >> Seville STS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Diagnostic Procedures >> Ignition Systems >> Electronic Ignition System Diagnosis >> Circuit Description
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit Description

There are two separate ignition module assemblies, one for each bank of cylinders. Each assembly contains an ignition control (IC) module and four ignition coils. Both IC modules consist of the following circuits:

Each ignition coil connects directly to its spark plug through a wire spring conductor housed in a short spark plug boot. The IC circuits transmit timing pulses from the Powertrain Control Module (PCM) to the IC modules which triggers the ignition coils in the proper sequence for spark plug firing. The PCM monitors each IC circuit for improper voltage levels. If an improper voltage level is detected on an IC circuit a DTC will set.