Electronic Ignition (EI) System

Electronic Ignition (EI) Inputs/Outputs:

CIRCUIT OPERATION
The ignition timing is controlled by the ECM to help maintain the best blend of engine performance and emissions under all operating conditions.

The ECM uses several sensors to calculate the amount of timing based on a map stored in its memory. The ECM varies the timing during:
^ Starting
^ Warm up
^ Idle
^ Hot engine operation
^ Acceleration
^ Low battery voltage
^ During fuel shut-off

Power Transistor Unit:

POWER TRANSISTOR
The power transistor, located near the crank angle sensor in the engine compartment, is a voltage amplifier that allows the signal sent from the ECM to activate the primary circuit in the ignition coil. This induces high voltage in the secondary windings of the ignition coils, providing spark to the plugs.