On the covered Kohler standby generator, Lo Crank Vlt means warning. Low cranking voltage — battery voltage dropped below 3.5 VDC during engine cranking. First, record whether the engine cranked slowly or not at all. Then: Kohler directs charging or replacing the battery.
Try in this order
0 of 6 completedWhat to do first
ReversibleRecord whether the engine cranked slowly or not at all.
Correct only the documented fault domain
ReversibleKohler directs charging or replacing the battery.
Measure the battery at rest
ReversibleWith the generator off, read the 12 V battery with a multimeter. A healthy battery reads about 12.4 V or more; a reading below that, or one that collapses when you try to start, is the usual cause.
Clean and tighten the terminals
ReversibleCorroded or loose battery terminals and harness ends raise resistance, and the voltage seen during cranking falls below the threshold even with a good battery. Clean them, tighten and try again.
Check the charger
ReversibleIf the battery is good but voltage stays low after charging, suspect the battery charger, its fuse or the wiring to it.
Judge the battery by more than its resting voltage
ReversibleA battery can read fine at rest and still collapse under the load of cranking. A shop load test, or watching the voltage on a meter while someone starts the set, shows whether it holds; one that falls to a few volts while cranking is finished whatever its resting reading.
Evidence ledger
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Exact questions
Common questions about “Kohler standby generator code Lo Crank Vlt”
What does Lo Crank Vlt mean on a Kohler standby generator?+
Warning. Low cranking voltage — battery voltage dropped below 3.5 VDC during engine cranking.
What voltage triggers Lo Crank Vlt on a Kohler generator?+
Kohler's fault table lists it as battery voltage dropping below 3.5 VDC during cranking, with the yellow fault lamp lit and the horn sounding. Other references describe the threshold as 60 percent of nominal for more than 6 seconds, so the exact figure depends on the controller.
How long does a Kohler generator battery last?+
Generator batteries commonly last two to four years depending on maintenance and use, so an older battery is the first suspect.
Can cold weather cause Lo Crank Vlt?+
Yes. Cold cuts a battery's output, so a battery that starts the set in summer can fail to in a freeze; replace a weak battery before winter.
Does the generator charge its own starting battery?+
Most standby sets keep the starting battery topped up with a built-in charger, so a battery that keeps going flat points to the charger, its fuse or the wiring as well as to the battery itself.
Will a Lo Crank Vlt warning stop the generator running?+
It is a warning, not a shutdown, but it means the next start may fail. Fix it before the next outage.