Engine Oil Pressure Sensor - Data Valid But Below Normal Operating Range
The CAT-CID100-FMI1 (Caterpillar) diesel fault code means: Engine Oil Pressure Sensor - Data Valid But Below Normal Operating Range. This is a serious severity code.
- Keep driving?
- No — stop driving
- DIY difficulty
- intermediate
- Estimated cost
- $300-$3000
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Common Symptoms
- Warning lamp or shutdown lamp
- Measured value below expected operating range
- Engine protect mode possible
Probable Causes (Ranked by Likelihood)
- Actual measured value truly low from mechanical issue Very Likely
- Sensor drift or out of calibration Likely
- Restriction, leak, or worn component in the measured system Likely
Frequently Asked Questions
What does CAT code CID100-FMI1 mean?
CAT code CID100-FMI1 (Engine Oil Pressure Sensor - Data Valid But Below Normal Operating Range) is a serious-severity fault on Caterpillar on-highway diesel engines. CID 100 is the Engine Oil Pressure Sensor, measuring engine oil pressure. FMI 1 (Data Valid But Below Normal Operating Range) 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 CID100-FMI1?
No. This fault can trigger engine protect mode, derate, or cause further damage. Park and diagnose before operating.
How much does it cost to fix CAT CID100-FMI1?
Typical repair is $300-$3000. 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
Confirm with CAT ET and note actual sensor reading versus expected range.
Verify the physical system (oil pressure, fuel pressure, etc.) with a mechanical gauge.
If mechanical reading matches sensor, fix the underlying mechanical fault.
If mechanical reading is normal but sensor reads low, replace sensor after verifying wiring and supply.
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
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