CAT-CID1835-FMI0 serious Caterpillar ›

DPF Soot Load Above Normal

The CAT-CID1835-FMI0 (Caterpillar) diesel fault code means: DPF Soot Load Above Normal. This is a serious severity code.

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Keep driving?
Short distances only
DIY difficulty
advanced
Estimated cost
$400-$3500
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What Are the Symptoms of CAT-CID1835-FMI0?

  • DPF warning lamp or HEST lamp
  • Forced regen required
  • Engine derate if regen not completed
  • Black smoke or poor fuel economy
  • Check Engine Light

What Causes CAT-CID1835-FMI0? (Most Likely First)

  • Excessive short-trip / idle operation preventing passive regen Very Likely
  • Failing or missed active regens Likely
  • DPF partially plugged with ash (requires cleaning/bake service) Likely
  • Faulty differential pressure sensor or sample lines plugged Likely
  • HC doser / aftertreatment injector not firing properly Possible
  • EGT sensors reading wrong, preventing regen authorization Possible

Can I Still Drive with CAT-CID1835-FMI0?

Short distances only. CAT-CID1835-FMI0 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.

Frequently Asked Questions

What does CAT CID1835-FMI0 mean?

CAT code CID1835-FMI0 (DPF Soot Load Above Normal) is a serious-severity aftertreatment fault on 2007-2010 C13/C15 ACERT engines. DPF soot loading too high. Regen may be disabled or failing.

How do I fix DPF issues on my CAT ACERT engine?

Run a CAT ET-commanded stationary regen first. If it fails or the DPF is ash-loaded (>100g typical), send the DPF out for cleaning/bake at a specialized shop. Verify EGT sensors, dP sensor, and the 7th/HC injector dose properly as part of diagnosis.

How much does it cost to fix CAT CID1835-FMI0?

DPF cleaning/bake service is $400-$800. Sensor replacement is $200-$600 installed. HC doser / 7th injector replacement is $800-$1500. A failed DPF substrate replacement is $2500-$3500 at a dealer.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose CAT-CID1835-FMI0?

  1. Connect CAT ET and read DPF soot load, ash load, and regen history.

  2. Inspect dP sensor and sample lines for soot blockage.

  3. Verify DPF inlet and outlet EGT sensors read matching at cold start.

  4. Command a stationary regen via CAT ET and monitor EGTs climbing as expected (target ~1100°F at DPF inlet).

  5. If stationary regen fails or ash load is high, DPF requires off-truck cleaning / bake service.

  6. Check HC doser / 7th injector operation for active regen events.

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)

Which Vehicles Commonly Get CAT-CID1835-FMI0?

  • Kenworth T800 with CAT C15
  • Kenworth W900 with CAT C15
  • Kenworth T2000 with CAT C15
  • Peterbilt 379 with CAT C15
  • Peterbilt 389 with CAT C15
  • Peterbilt 386 with CAT C15
  • Peterbilt 387 with CAT C15
  • Freightliner Classic XL with CAT C15

Explore More

More Caterpillar codes → Diesel home All diesel codes Heavy-duty Guides

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