Operation CHARM: Car repair manuals for everyone.

Ignition System: Description and Operation

Ignition Circuit:






This vehicle uses an electronic ignition system with computer controlled spark timing. Components include:

^ Ignition coil.
^ Camshaft driven distributor with crank angle sensor.
^ Igniter.
^ Distributor cap and rotor.
^ High voltage resistor type (radio static suppressor) ignition wires.


Sensors in the distributor indicate crankshaft position and engine speed. The ECU monitors these signals, along with signals from other engine sensors, to determine ignition timing. When the key is turned "ON," current is supplied to the coil primary windings and grounded through the igniter. The igniter contains a power transistor. The ECU signals the igniter to switch ignition coil primary current "ON" and "OFF", firing the coil. Distributor cap and rotor distribute spark voltage to the correct spark plugs.