System Description

The ignition system provides timing control in accordance with the engine management strategy and powertrain sensor inputs; the system consists of:

engine control module
ignition coils supply relay
ignition control modules
ignition coils
spark plugs

Engine Control Module (ECM)
Provides triggering for the ignition control modules to control individual firing of the spark plugs supplies ground for the ignition coils supply relay

Ignition Coils Supply Relay
The ignition coils supply relay is located in the engine and transmission control module compartment.

The ECM switches a ground to the coil of the ignition coils supply relay; the relay energizes and switches a 12v supply to the ignition control modules and the ignition coils.