Power Module
The ignition power module receives power from the ignition switch in "START" and "RUN" positions through terminal "A" of connector No. 1. See Figure. The ECU and terminal "B" of of connector No. 1 are grounded to the engine block near the starter motor.
Terminal "B" of connector No. 2 receives a signal from pin No. 27 of the ECU. This signal causes the ignition power module circuitry to charge the coil primary windings. The ignition power module will open the windings upon coil saturation and induce high voltage in the secondary windings. Ignition timing is controlled by the ECU through pin "B" of connector No. 2.