Kohler Comand Pro CH1000 Service Manual page 58

Section 7
Electrical System and Components
a. If the problem is gone, the electrical system
on the unit is suspect. Check the key switch,
wires, connections, safety interlocks, etc.
b. If the problem persists, the condition is
associated with the ignition or electrical
system of the engine. Leave the kill lead
isolated until all testing is completed.
2. Test for spark on both cylinders with Kohler
ignition tester (see Section 2). Disconnect one
spark plug lead and connect it to the post
terminal of the tester. Connect the clip to a good
ground, not to the spark plug.
Crank the engine and observe the tester spark
gap. Repeat the procedure on the other cylinder.
Remember to reconnect the fi rst spark plug lead.
a. If one side is not fi ring, check all wiring,
connections, and terminations on that side. If
wiring is okay, replace ignition module and
retest for spark.
b. If the tester shows spark, but the engine
misses or won't run on that cylinder, try a
new spark plug.
c. If neither side is fi ring, recheck position of
ignition switch and check for shorted kill
lead.
7.6
Operation of DSAI Ignition Systems
DSAI Ignition System Explanation
A digital spark advance ignition system (DSAI) is
used on some models. The DSAI ignition system is an
advanced, 12-volt version of the fi xed timing ignition
system used on other models. Two inductive-style
ignition modules control the ignition timing based on
engine RPM. A typical DSAI application (Figure 7-6)
consists of the following components:
• A magnet assembly, which is permanently affi xed
to the fl ywheel.
• Two inductive, 12-volt ignition modules, which
mount on the engine crankcase (Figure 7-6).
• A 12-volt batt ery, which supplies current to the
ignition modules.
• A kill switch (or key switch) which grounds the
spark advance module to stop the engine.
• Two spark plugs.
Operation
The system provides more consistent energy to the
spark plugs at all engine speeds by using the 12-volt
batt ery as its source of power. Engine speed and top
dead center (TDC) location reference information
is provided by the fl ywheel magnet group as it
passes the ignition module. System triggering and
engine timing is performed by a digitally-controlled
microprocessor. This digital control provides
repeatable and consistent engine cylinder spark
timing. Each DSAI module performs its function
independently for each engine cylinder.