Electrical System
64
19 690 01 Rev. --
KohlerEngines.com
Condition
Conclusion
20/25 amp
OK (green) light comes on and stays steady.
Disconnect tester black lead attached to 1 AC terminal
and reconnect it to other AC terminal. Repeat test. If OK
(green) light comes on again, part is good and may be
used.
NOTE: A
fl
ashing LOW light can also occur as a result of
an inadequate ground lead connection. Make
certain connection location is clean and clamp is
secure.
Other lights come on.
Recti
fi
er-regulator is faulty and should not be used.
Troubleshooting Guide
20/25 Amp Battery Charging System
NOTE: Always zero ohmmeter on each scale before
testing to ensure accurate readings. Voltage
tests should be made with engine running at
3600 RPM - no load. Battery must be good and
fully charged.
When problems occur in keeping battery charged or
battery charges at too high a rate, problem can usually
be found somewhere in charging system or with battery.
To test charging system for no charge to battery:
1. Insert an ammeter in B+ lead from recti
fi
er-regulator.
With engine running at 3600 RPM and B+ (at
terminal on recti
fi
er-regulator) to ground using a DC
voltmeter.
If voltage is 13.8 volts or more, place a minimum
load of 5 amps (turn on lights if 60 watts or more, or
place a 2.5 ohm, 100 watt resistor across battery
terminals) on battery to reduce voltage. Observe
ammeter.
Condition
Conclusion
Charge rate increases
when load is applied.
Charging system is OK
and battery was fully
charged.
Charge rate does not
increase when load is
applied.
Test stator and recti
fi
er-
regulator (steps 2 and 3).
2. Remove connector from recti
fi
er-regulator. With
engine running at 3600 RPM, measure AC voltage
across stator leads using an AC voltmeter.
Condition
Conclusion
Voltage is 28 volts or
more.
Stator is OK. Recti
fi
er-
regulator is faulty; replace.
Voltage is less than 28
volts.
Stator is faulty; replace.
Test stator further using an
ohmmeter (steps 3 and 4).
3. With engine stopped, measure resistance across
stator leads using an ohmmeter.
Condition
Conclusion
Resistance is 0.064/0.2
ohms.
Stator is OK.
Resistance is 0 ohms.
Stator is shorted; replace.
Resistance is in
fi
nity
ohms.
Stator is open; replace.
4. With engine stopped, measure resistance from each
stator lead to ground using an ohmmeter.
Condition
Conclusion
Resistance is in
fi
nity ohms
(no continuity).
Stator is OK (not shorted
to ground).
Resistance (or continuity)
measured.
Stator leads are shorted to
ground; replace.
To test charging system for battery continuously charging
at high rate:
1. With engine running at 3600 RPM, measure voltage
from B+ lead to ground using a DC voltmeter.
Condition
Conclusion
Voltage is 14.7 volts or
less.
Charging system is OK.
Battery is unable to hold
charge; service or replace.
Voltage is more than 14.7
volts.
Faulty recti
fi
er-regulator;
replace.
