There are 3 dual-tower ignition coils that are part of the ignition control module (ICM). The ICM contains coil driver circuits that command the coils to operate. The ICM has the following circuits:

The engine control module (ECM) controls each dual-tower ignition coil by transmitting timing pulses on the ignition coil control circuit to the ICM for the proper coil to enable a spark event.

Inspect the spark plug wires for proper orientation.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electronic Ignition (EI) System Description

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Special Tools Required

J 26792 Spark Tester

Important: The engine may start and run until all fuel is removed from the fuel line.

1. With the ignition OFF, remove the fuel pump relay.
2. Crank the engine and test for a strong spark on each cylinder spark plug wire using the J 26792 . Ground the companion cylinder spark plug wire of each cylinder when it is tested.

⇒	If a strong bright blue spark is present on all 6 of the cylinders, remove and inspect all of the spark plugs for proper torque, proper gap, wear, damage, and fouling. Refer to Spark Plug Wire Inspection.

⇒	If there is no spark on any of the cylinders, test the ignition voltage circuit of the ICM for an open/high resistance or short to ground, or test the ground circuit of the ICM for an open/high resistance, or a faulty ICM.

⇒	The wire circuit resistance should measure less than 3 ohms.

⇒	If spark is present on one or more of the cylinders, inspect and test the spark plug wires for arcing, cuts, rubbing on other components, and proper resistance, or a faulty ICM.

⇒	If all tests are normal, then the system is operating correctly.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.