Kohler command pro CH940 Service Manual page 46

Electrical System
Check Ignition Modules and Connections (CDI/MDI only)
1. Remove blower housing from engine. Inspect kill wire for any damage, cuts, or shorts to engine or ignition module
body. Check that connections are oriented properly on terminals of modules.
2. On MDI adjustable timing engines, ensure that both modules are correctly installed with flat side of module out/
towards you.
Condition
All checks are OK but module has no
spark or fails to advance.
Test Timing Advance (DSAI only)
1. Make a line near edge of flywheel screen with a marking pen, chalk, or narrow tape.
2. Connect an automotive timing light to cylinder that had good spark.
3. Run engine at idle and use timing light beam to locate line on screen. Draw a line on blower housing next to line
on screen. Accelerate to full throttle and watch for movement of line on screen relative to line on blower housing.
If both cylinders had good spark, repeat test on other cylinder.
Condition
Line on screen did not move away
from line on blower housing during
acceleration.
Lines made on blower housing not
90° apart.
Test Ignition Modules and Connections (DSAI only)
1. Remove blower housing from engine. Inspect wiring for any damage, cuts, bad crimps, loose terminals, or broken
wires. Check that connections are oriented properly on terminals of modules.
2. Disconnect leads from ignition module(s) and clean all of terminals (male and female) with aerosol electrical
contact cleaner to remove any old dielectric compound, dark residue, dirt, or contamination. Disconnect spark
plug leads from spark plugs.
3. Using a multi-meter, check that a proper ground is established between ground (black) lead of DSAI module
(closest to spark plug lead) and a known good ground location on engine.
4. Turn key switch to ON position and check for 12 volts at center/power (red) lead terminal of DSAI module. Use
same ground location for multi-meter as in checking for timing advance.
Condition
All tests are OK but module has no
spark or fails to advance.
Any test is BAD.
46
Possible Cause
Ignition Module
Possible Cause
Ignition
Possible Cause
Ignition Module
Ignition Module or Connections
KohlerEngines.com
Conclusion
Replace affected module.
Conclusion
Test ignition modules and
connections.
Conclusion
Replace affected module.
Determine cause and fix as required;
retest.
62 690 01 Rev. J