Cummins fault code 612
High Lubricating Oil Filter Restriction: reading below normal (most severe)
What it means
Cummins' description: High Lubricating Oil Filter Restriction.
SPN 99 is High Lubricating Oil Filter Restriction. FMI 1 means the sensor is working, but the value it reports is far below where it should be. This is the most severe 'low' level.
The ECM monitors oil pressure, oil temperature and, on some engines, oil level. Low oil pressure is one of the fastest ways to destroy an engine, so Cummins treats it very seriously.
What the lamp means
A red stop lamp means Cummins treats this as serious. Stop the engine as soon as you can do it safely and get it checked before running it again.
Green, yellow, red: three ways this can look
The same code can be a quick fix or a reason to shut down. Match your situation to the closest example. Cummins rates this a red stop lamp code, so if the red lamp is on, go by the red example.
Keep an eye on it
An oil change reminder, or a sensor code where the gauge reads normal and the level is full.
Schedule a repair
Oil level low or a sensor code that keeps coming back. Top off and get it checked soon, and don't ignore oil consumption.
Stop and get help
Low oil pressure warning, gauge near zero, knocking, or a stop lamp. Shut the engine off immediately. Every second of low oil pressure damages bearings.
Common causes
The sensor reading itself is out of range or the condition is real, so look at the system:
- Low oil level
- Wrong oil viscosity or diluted oil (fuel or coolant in the oil)
- Worn oil pump or bearings
- Clogged oil filter or pickup
- Real high oil temperature from heavy load or a cooling problem
What you can check before calling
- Check the oil level with the engine off and level
- Look at the oil for milky color (coolant) or a fuel smell
- Note whether the oil gauge drops at hot idle
Clearing the code without fixing the cause usually brings it right back, and on emissions systems it can restart derate timers.
Engines and sources
Cummins uses the same fault code numbers across its electronic engines, including on-highway models like the ISB/B6.7, ISL/L9 and ISX/X15, though not every code applies to every engine or software level. Source: Diagnostic Fault Codes for Cummins Engines. Always confirm with Cummins service information (QuickServe) for your engine serial number.
Related Engine oil codes
- 649 SPN 1378 FMI 31
Engine Oil Change Interval: condition exists - 688 SPN 98 FMI 0
Engine Oil Level: reading above normal (most severe) - 473 SPN 1380 FMI 2
Engine Oil Level #2 Low: erratic or intermittent signal - 471 SPN 98 FMI 17
Engine Oil Level: reading below normal (least severe) - 435 SPN 100 FMI 2
Engine Oil Rifle Pressure: erratic or intermittent signal - 425 SPN 175 FMI 2
Engine Oil Temperature: erratic or intermittent signal
Look up another code
Cummins fault code (like 1922), J1939 SPN and FMI (like SPN 3251 FMI 0), or an OBD-II code (like P0420).
Questions
What does Cummins fault code 612 mean?
Cummins fault code 612 is J1939 SPN 99 FMI 1: High Lubricating Oil Filter Restriction. In plain terms: high lubricating oil filter restriction: reading below normal (most severe).
Can I keep driving with Cummins code 612?
No. Cummins assigns this code a red stop lamp. Stop the engine as soon as it's safe and have it checked before running it again. Look at the green, yellow and red examples on this page to judge your situation.
What is the SPN and FMI for Cummins code 612?
SPN 99 identifies the part or system (High Lubricating Oil Filter Restriction). FMI 1 describes the type of failure: reading below normal (most severe).
What usually causes Cummins code 612?
The most common causes are: low oil level; wrong oil viscosity or diluted oil (fuel or coolant in the oil); worn oil pump or bearings.
Diesel down in the Midlands?
We work on Cummins-powered pickups, vans and medium-duty trucks across Lexington, Columbia and the Midlands, on site at your yard or roadside.