Kohler generator code Engine Oil Pressure Low
High severity — The low-oil-pressure (LOP) switch indicated low oil pressure for more than about 5 seconds, so the controller shut the engine down.
Applies to: Kohler residential standby generators with an RDC2 or DC2 controller
What it means
Five seconds. That's the entire delay Kohler builds into this shutdown, because an engine actually running without oil pressure can suffer real internal damage in well under a minute. A low-oil-pressure (LOP) switch threaded into the engine block closes once pressure drops below its calibrated point, and after the RDC2 or DC2 controller sees that signal held for roughly five seconds, it kills the engine immediately rather than waiting to see whether pressure recovers on its own. This is one of the few Kohler faults where the controller is arguably more cautious than a human operator would be, and that's intentional — an oil pressure fault is treated as an emergency stop, not a warning to keep an eye on.
Most common causes
A handful of things can trip this switch, and not all of them mean the engine is actually damaged:
- Oil level low or oil overdue for a change
- Failed LOP switch or wiring
- Clogged oil filter
- Internal engine wear
What you can check yourself
Here's the safe homeowner-level check, in order:
- Check oil level on the dipstick once the engine has cooled and top off with the manufacturer-specified oil grade
- Inspect for visible leaks at the filter, drain plug, or gaskets
- Clear the fault and retest only after confirming oil level is correct
If the dipstick reads full and there's no obvious leak, resist the urge to just keep restarting the unit — a fault that comes back quickly after a normal-looking oil level is telling you the pressure reading itself, not the oil supply, is the actual problem.
All codes for this brand
Every Kohler generator fault code — full list with what differs between models.
Related codes: Over Crank and High Engine Temperature — both are protective engine shutdowns triggered the same way. See the Low Oil Pressure Shutdown symptom page for more context.