System Description

The ignition system used for this vehicle has an ESA (Electronic Spark Advance) system and consists of the following parts.

^ ECM
It detects the engine condition through the signals from the sensors, determines the most suitable ignition timing and time for electricity to flow to the primary coil and sends a signal to the igniter.
^ Igniter (Power unit)
It turns ON and OFF the primary current of the ignition coil according to the signal from ECM.
^ Ignition coil
When the ignition coil primary current is turned OFF, a high voltage is induced in the secondary winding.
^ Distributor
It distributes a high voltage current to each plug.
^ High-tension cords and spark plugs
^ CMP sensor (Camshaft Position Sensor)
Located in the distributor, it converts the crank angle into voltage variation and sends it to ECM.
^ MAF sensor, TP sensor, ECT sensor, IAT sensor, VSS, engine start switch and test switch terminal.
In ESA system, the ECM is programmed for the best ignition timing under every engine condition. Receiving signals which indicate the engine condition from the sensors, e.g., engine revolution, intake air volume, coolant temperature, etc., it selects the most suitable ignition timing from its memory and operates the igniter.
Thus ignition timing is controlled to yield the best engine performance.