1997+ Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-826148R2, Page 66Get this manual
Ignition Coil Circuit As the capacitor voltage flows through the primary windings of the ignition coil, voltage is induced into the ignition coil secondary windingsThis secondary voltage rises to the level required to jump the spark plug gap and return to groundThis secondary voltage can, if necessary, reach approximately 40,000 voltsTo complete the secondary voltage path, the released voltage enters the ground circuit of CDM moduleS NS