Engine Speed / Crankshaft Sensor - Data Erratic, Intermittent, or Incorrect
The CAT-CID190-FMI2 (Caterpillar) diesel fault code means: Engine Speed / Crankshaft Sensor - Data Erratic, Intermittent, or Incorrect. This is a serious severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- intermediate
- Estimated cost
- $200-$800
Down with a CAT fault on the road?
Get connected with a verified mobile diesel mechanic near you. Verified diesel & reefer techs, launching on the freight corridor.
Find a mobile mechanic →A $30 car code reader can't do diesel. The HD7000 reads full-system codes and does parked DPF regen, idle/speed-limit, and service resets from the cab — on everything from a 6.7 Cummins/Power Stroke/Duramax pickup to Class-8 trucks (Detroit, Paccar, CAT, Volvo, Mack, International).
Full-system 6/9/16-pin diesel scan tool for Cummins, Paccar, CAT, Detroit and more — plug-and-play, no subscription. A cheaper way to read heavy-duty codes a basic OBD2 scanner skips entirely.
Affiliate links — we earn a commission at no extra cost to you.
Common Symptoms
- Intermittent Check Engine Light
- Erratic or fluctuating signal on CAT ET
- Possible stumble or momentary power loss
Probable Causes (Ranked by Likelihood)
- Intermittent wiring fault from chafe or loose pin Very Likely
- Failing sensor producing noise Likely
- EMI or ground noise or bad ECM ground Possible
Frequently Asked Questions
What does CAT code CID190-FMI2 mean?
CAT code CID190-FMI2 (Engine Speed / Crankshaft Sensor - Data Erratic, Intermittent, or Incorrect) is a serious-severity fault on Caterpillar on-highway diesel engines. CID 190 is the Engine Speed / Crankshaft Sensor, measuring primary crank speed signal. FMI 2 (Data Erratic, Intermittent, or Incorrect) indicates the specific fault mode. Use CAT ET to confirm before replacing parts. Diagnose with CAT ET (Electronic Technician) software.
Can I drive my truck with CAT code CID190-FMI2?
Short distances may be acceptable, but running long with this fault risks progressive damage or forced derate. Address promptly.
How much does it cost to fix CAT CID190-FMI2?
Typical repair is $200-$800. Sensor / wiring fixes fall at the low end; injector, HEUI pump, turbo, or aftertreatment work falls at the high end. CAT dealer labor often requires CAT ET for calibration and parameter programming.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
Wiggle-test the harness and connector while watching live data on CAT ET for dropouts.
Back-probe the signal pin and measure during operation; erratic readings confirm the circuit or sensor.
Inspect connector pin tension and replace the sensor if harness checks good.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J1939-73Application Layer: Diagnostics (defines the SPN/FMI fault-identifier framework)
Commonly Affected Vehicles
- Freightliner Classic XL with CAT C15
- Peterbilt 335 with CAT C7
- Peterbilt 386 with CAT C15
- Kenworth T800 with CAT C15
- Western Star 5900 with CAT C15
- Peterbilt 389 with CAT C15
- Peterbilt 387 with CAT C15
- Kenworth T470 with CAT C9
- Kenworth T800 with CAT C13
- Peterbilt 386 with CAT C13
- Thomas / Bluebird school bus with CAT C7
- Peterbilt 387 with CAT C13
- Peterbilt 340 with CAT C9
- Peterbilt 379 with CAT C15
- Kenworth T370 with CAT C7
- Kenworth T660 with CAT C13
- International 9400i with CAT C15
- Kenworth W900 with CAT C15
- Freightliner Columbia with CAT C13
- International 9200i with CAT C13
- International 4300 with CAT C7
- Western Star 4900 with CAT C15
- Freightliner M2 106 with CAT C7
- IC Bus shuttle with CAT C7
- International 9200i with CAT C15
- Kenworth T2000 with CAT C15
Related Codes
Explore More
Was this helpful?
Send this to whoever is fixing the truck — your tech, or the person asking what the fault means.