Ignition System: Testing and Inspection

CIRCUIT DESCRIPTION
This distributorless ignition system consists of two coil packs, a crankshaft position (CKP) sensor, and the engine control module (ECM). The ECM performs all of the ignition control (IC) module functions. The ignition coil assembly has voltage supplied by an ignition feed circuit and also contains a dedicated ground circuit. The remaining three circuits go to the ECM and are the IC circuits. The ECM causes a spark to occur by pulsing an IC circuit, which triggers an ignition coil and fires the appropriate spark plug. The ECM controls the sequencing and the timing internally.

TEST DESCRIPTION

Steps 1-5:

Steps 6-7:

Steps 8-11:

Steps 12-16:

Steps 17-20:

Steps 21-22:

The numbers below refer to the step numbers on the diagnostic table.
6. The spark tester should show steady, consistent spark across the tip of the spark tester when using the scan tool to operate the coil.
7. This step tests the diode in the secondary side of the coil and the continuity of the ground circuit inside the coil. You should be able to read continuity in one direction only.
10. This step is to verify the operation of the ignition coil control circuit and the driver in the ECM.