Installation manual

90-898305

6-4

Ignition System - V6 Models

Theory of Operation

When the ignition key is turned to the RUN position, battery voltage is applied

to the main relay through the PURPLE wire. The main relay is then closed and

D.C. current from the battery or charging system is transferred through the

main relay 20 Amp fuse to the positive terminal of all 6 ignition coil primary

windings. The negative terminal of the coil primary is connected to engine

ground through the Electronic Control Module (ECM). When this circuit is

closed, a magnetic field is allowed to be built up in the ignition coil. The Crank

Position Sensor senses the location of the teeth on the flywheel and supplies

a trigger signal to the ECM. When the ECM receives this signal, the ECM will

then open the ground circuit of the coil primary. The magnetic field in the

ignition coil primary will then collapse cutting across the coil secondary

winding creating a high voltage charge (50,000 volts) that is sent to the spark

plug.

Coil Driver

Model Year 2001 and Up

The ECM sends a 5 VDC pulse to the coil driver mounted on each ignition

coil. Which coil driver receives this pulse is determined by the ECM receiving

a signal from the crank position sensor.

When the coil driver receives its ECM pulse (signal), it closes its circuit which

allows the primary side of the ignition coil to build up energy which it initially

receives from the boat battery.

When the ECM pulse (signal) to the coil driver drops below 1.3 volts, the coil

driver opens its circuit which causes the primary field of the ignition coil to

collapse. This field collapse induces a voltage buildup in the secondary

winding of the ignition coil resulting in a potential voltage of up to 50,000 volts

at the spark plug.

Notes

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