Galant L4-2.0L SOHC (1989)
Ignition Coil: Testing and Inspection
Operation
When the ignition power transistor unit is switched ON by the signals from the engine control module, the primary current of the ignition coil will
flow. When the ignition power transistor unit is switched OFF, the primary current tlow is interrupted, and high voltage is produced at the secondary
coil.
When the engine control module switches OFF the power transistor within the unit, the battery voltage within the unit is applied to the ignition power
transistor unit, and the ignition power transistor unit is switched ON In addition, the power transistor unit is switched OFF when the engine control
module switches ON the power transistor within the unit.
Inspection
Using Oscilloscope
1. Primary signal of ignition coil
(1) Run the engine at an idle revolution speed.
(2) Connect the probe to oscilloscope pick-up point 1 as shown in the circuit diagram, and check the primary signal of the ignition coil.
