Cummins fault code 3385
Intake Manifold 1 Temperature: reading below normal (moderately severe)
What it means
Cummins' description: Intake Manifold 1 Temperature - Data Valid But Below Normal Operating Range - Moderately Severe Level.
SPN 105 is Engine Intake Manifold 1 Temperature. FMI 18 means the value is clearly below normal operating range. It's the middle 'low' level.
These sensors measure the air coming into the engine: intake manifold temperature, charge air cooler outlet temperature, ambient temperature, barometric pressure, humidity and air filter restriction. The ECM uses them to calculate fueling and timing.
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
A one-time sensor code with normal power and temperatures.
Schedule a repair
Amber lamp, rough cold starts, or the code returns. Usually a sensor or connector. Book it so fueling stays correct.
Stop and get help
Several sensor codes at once with a stop lamp or no-start. That can point to a shared sensor supply or ECM problem. Get it diagnosed before driving.
Common causes
The sensor reading itself is out of range or the condition is real, so look at the system:
- Clogged air filter
- Dirty or blocked charge air cooler or radiator fins
- Real high intake temperature in hot weather or under heavy load
- Boost leak changing intake readings
What you can check before calling
- Check the air filter and the restriction indicator
- Clean bugs and debris from the front of the charge air cooler
- Look for unplugged or damaged connectors on intake sensors
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
- 153 SPN 105 FMI 3
Intake Manifold 1 Temperature Sensor Circuit: circuit voltage high / shorted high - 154 SPN 105 FMI 4
Intake Manifold 1 Temperature Sensor Circuit: circuit voltage low / shorted low - 155 SPN 105 FMI 0
Intake Manifold 1 Temperature: reading above normal (most severe) - 436 SPN 105 FMI 2
Intake Manifold 1 Temperature: erratic or intermittent signal - 488 SPN 105 FMI 16
Intake Manifold 1 Temperature: reading above normal (moderately severe) - 2964 SPN 105 FMI 15
Intake Manifold 1 Temperature: reading above normal (least severe)
Related Intake air and environment sensors codes
- 3367 SPN 4490 FMI 9
Specific Humidity Sensor: abnormal update rate - 3341 SPN 107 FMI 16
Engine Air Filter Differential Pressure: reading above normal (moderately severe) - 3478 SPN 2630 FMI 2
Engine Charge Air Cooler Outlet Temperature: erratic or intermittent signal - 3531 SPN 171 FMI 9
Ambient Air Temperature: abnormal update rate - 2572 SPN 2630 FMI 4
Engine Charge Air Cooler Outlet Temperature: circuit voltage low / shorted low - 2571 SPN 2630 FMI 3
Engine Charge Air Cooler Outlet Temperature: circuit voltage high / shorted high
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 3385 mean?
Cummins fault code 3385 is J1939 SPN 105 FMI 18: Intake Manifold 1 Temperature - Data Valid But Below Normal Operating Range - Moderately Severe Level. In plain terms: intake manifold 1 temperature: reading below normal (moderately severe).
Can I keep driving with Cummins code 3385?
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 3385?
SPN 105 identifies the part or system (Engine Intake Manifold 1 Temperature). FMI 18 describes the type of failure: reading below normal (moderately severe).
What usually causes Cummins code 3385?
The most common causes are: clogged air filter; dirty or blocked charge air cooler or radiator fins; real high intake temperature in hot weather or under heavy load.
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.