Ignition Control Module: Description and Operation
Power Transistor:
PURPOSE
The power transistor controls ignition current by interrupting the ignition coil primary ground causing secondary circuit discharge.
Power Transistor Location:
LOCATION
The power transistor is located on the intake manifold.
Ignition Timing Control System:
OPERATION
The ECU controls ignition timing through the power transistor. The power transistor is a type of switch that allows a very low voltage (from the ECU) to control a larger amount of voltage (negative side of coil).