Cummins fault code 425
Engine Oil Temperature: erratic or intermittent signal
What it means
Cummins' description: Engine Oil Temperature - Data erratic, intermittent or incorrect.
SPN 175 is Engine Oil Temperature 1. FMI 2 means the signal is jumping around, dropping in and out, or doesn't make sense compared to other readings.
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
An amber (yellow) warning lamp means the engine can usually keep running, but the fault should be repaired soon, ideally the same day.
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.
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
Listed by Cummins for: QSX 15, QSG 12. 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: Cummins Tier 4 Fault Codes. Always confirm with Cummins service information (QuickServe) for your engine serial number.
Same SPN, other failure types
- 212 SPN 175 FMI 3
Engine Oil Temperature Sensor 1 Circuit: circuit voltage high / shorted high - 213 SPN 175 FMI 4
Engine Oil Temperature Sensor 1 Circuit: circuit voltage low / shorted low - 214 SPN 175 FMI 0
Engine Oil Temperature: reading above normal (most severe) - 421 SPN 175 FMI 16
Engine Oil Temperature: reading above normal (moderately severe) - 6524 SPN 175 FMI 3
Engine Oil Temperature Sensor 1 Circuit: circuit voltage high / shorted high - 6525 SPN 175 FMI 4
Engine Oil Temperature Sensor 1 Circuit: circuit voltage low / shorted low
Related Engine oil codes
- 415 SPN 100 FMI 1
Engine Oil Rifle Pressure: reading below normal (most severe) - 435 SPN 100 FMI 2
Engine Oil Rifle Pressure: erratic or intermittent signal - 471 SPN 98 FMI 17
Engine Oil Level: reading below normal (least severe) - 473 SPN 1380 FMI 2
Engine Oil Level #2 Low: erratic or intermittent signal - 253 SPN 98 FMI 1
Engine Oil Level: reading below normal (most severe) - 252 SPN 98 FMI 2
Engine Oil Level #1 Sensor Circuit: 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 425 mean?
Cummins fault code 425 is J1939 SPN 175 FMI 2: Engine Oil Temperature - Data erratic, intermittent or incorrect. In plain terms: engine oil temperature: erratic or intermittent signal.
Can I keep driving with Cummins code 425?
Usually for a short time, if the engine runs normally and no other warnings are on. Get it diagnosed soon, because many amber codes lead to a derate if ignored. Look at the green, yellow and red examples on this page to judge your situation.
What is the SPN and FMI for Cummins code 425?
SPN 175 identifies the part or system (Engine Oil Temperature 1). FMI 2 describes the type of failure: erratic or intermittent signal.
What usually causes Cummins code 425?
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.