DURAMAX-P24A2 serious Duramax ›

Diesel Particulate Filter Active / Passive Regeneration Incomplete

The DURAMAX-P24A2 (Duramax) diesel fault code means: Diesel Particulate Filter Active / Passive Regeneration Incomplete. This is a serious severity code.

Unverified. We could not confirm this code's definition against freely available manufacturer documentation, so treat the meaning, severity and fix guidance on this page as unconfirmed. Check it against the manufacturer's service information for your exact model and serial range before acting on it. This page is kept out of search engines for that reason, and we are working through this family manual by manual.

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Keep driving?
Yes, with caution
DIY difficulty
intermediate
Estimated cost
$100-$3,500
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What Are the Symptoms of DURAMAX-P24A2?

  • Check Engine Light illuminated
  • Performance loss or rough running (if engine-related)
  • Warning message on dash (DPF/DEF-related)
  • Limp mode under certain conditions
  • Possible hard starting or stalling

What Causes DURAMAX-P24A2? (Most Likely First)

  • Regen did not complete in time Very Likely
  • Wiring harness abrasion / connector corrosion Likely
  • Sensor end-of-life (high-mileage trucks) Possible
  • Related upstream fault (e.g., low battery voltage, ground fault) Possible

Can I Still Drive with DURAMAX-P24A2?

Yes, with caution. DURAMAX-P24A2 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.

Frequently Asked Questions

What is P24A2 on a Duramax?

Duramax code P24A2 (Diesel Particulate Filter Active / Passive Regeneration Incomplete) is a serious-severity diagnostic trouble code triggered by the engine control module when it detects a problem in the associated system. Duramax trucks accumulate soft-fault codes — clear them and retest rather than throwing parts at recurring-but-harmless DTCs.

Is a Duramax P24A2 safe to drive?

Depends on severity. Critical codes (fuel pressure, PCM, overtemp) need immediate attention. Sensor codes are usually OK short-term.

How much does it cost to fix P24A2 on a Duramax?

Estimated repair cost $100-$3,500. Scan first — cascaded codes often share a single root cause.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose DURAMAX-P24A2?

  1. Scan all modules — a single failure often sets codes in multiple modules

  2. Capture freeze frame and compare to known operating ranges

  3. Back-probe the associated sensor/actuator with a DMM

  4. Inspect wiring and connectors at both ends of the affected circuit

  5. Clear code, perform a complete drive cycle, and verify the fault is fixed

Sources 1

This page is built from documented references. Verify against your own service info before repair work.

  • SAE J2012Diagnostic Trouble Code Definitions (defines P24A2 as a generic OBD-II code)

Which Vehicles Commonly Get DURAMAX-P24A2?

  • 2007.5-2010 Chevy Silverado 2500/3500 HD 6.6L Duramax LMM
  • 2007.5-2010 GMC Sierra 2500/3500 HD 6.6L Duramax LMM
  • 2011-2016 Chevy Silverado 2500/3500 HD 6.6L Duramax LML
  • 2011-2016 GMC Sierra 2500/3500 HD 6.6L Duramax LML
  • 2017+ Chevy Silverado 2500/3500 HD 6.6L Duramax L5P
  • 2017+ GMC Sierra 2500/3500 HD 6.6L Duramax L5P

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

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