Operation - BRP 2995 Johnson Service Manual

OPERATION
IGNITION SYSTEM
OPERATION
The ignition system is a condenser discharge type. The condenser built in the COl unit stores the electri-
cal energy generated by the condenser charge coil.
The electrical energy stored in the condenser is released to the ignition coil primary windings by the igni-
tion timing signal calculated by the COl unit from the pulser coil signal.
Ignition timing varies based upon engine speed . Timing is fixed at 10° ATDC until the engine starts. Tim-
ing then varies from 5° ATDC to 30° BTDC based on engine speed.
Engine stop switch
Condenser
charge coil
Pulser coil
Neutral switch
~
CPU
Oil pressure
~)----o-----IL...-""::""--'
switch
Jr '--- ----- ____________
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1. Power source circuit (Charging circuit)
2. Power source circuit
3. Base signal circuit
4. Hardware ignition signal circuit
5. Software ignition signal contol circuit
6. Input circuit
7. Input circuit
8. Output circuit
9. Output circuit
Ignition coil
Caution lamp
Tachom eter
95
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