DURAMAX-P0206 serious Duramax ›

Injector Circuit / Open — Cylinder 6

The DURAMAX-P0206 (Duramax) diesel fault code means: Injector Circuit / Open — Cylinder 6. This is a serious severity code.

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Keep driving?
Yes, with caution
DIY difficulty
intermediate
Estimated cost
$400-$900 per injector (LB7 often needs all 8 done; $3,000-$5,500 total)
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What Are the Symptoms of DURAMAX-P0206?

  • Rough idle or misfire at idle
  • White or black smoke from exhaust
  • Reduced power / limp mode
  • Hard starting or long cranking
  • Check Engine Light illuminated

What Causes DURAMAX-P0206? (Most Likely First)

  • Failed injector solenoid on cylinder 6 (LB7 notorious for this) Very Likely
  • Open or damaged injector harness wiring to cylinder 6 Likely
  • Corroded valve cover pass-through connector (LB7 under-valve-cover harness) Likely
  • FICM or injector driver module fault Possible

Can I Still Drive with DURAMAX-P0206?

Yes, with caution. DURAMAX-P0206 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.

Frequently Asked Questions

What is P0206 on a Duramax?

Duramax code P0206 (Injector Circuit Open — Cylinder 6) is a serious-severity diagnostic trouble code triggered by the engine control module when it detects a problem in the associated system. On LB7 Duramax engines (2001-2004) this code is almost always caused by cracked injector solenoid balls — a GM service campaign covered some of them but not all.

Is a Duramax P0206 safe to drive?

Yes, briefly. You can drive short distances at low load to reach a shop, but extended operation with a dead cylinder can wash down the cylinder wall with diesel fuel, diluting the oil and damaging bearings.

How much does it cost to fix P0206 on a Duramax?

Individual injector replacement runs $400-$900 parts and labor. On LB7 engines, dealers and indies almost always recommend replacing all 8 injectors at once, bringing the bill to $3,000-$5,500. The job requires removing the valve covers and the injector hold-downs.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose DURAMAX-P0206?

  1. Scan for balance rates on all 8 cylinders; cylinder 6 balance outside ±4 mm³ confirms injector issue

  2. Remove valve cover and inspect under-valve-cover harness for fuel saturation (classic LB7 failure)

  3. Measure injector solenoid resistance at ECM side — should be ~0.5-2.0 ohms. Open indicates injector or harness fault

  4. Back-probe the injector connector at the valve cover pass-through and repeat test to isolate harness vs. injector

  5. Replace faulty injector and re-learn balance rates with Tech 2 or equivalent scan tool

Sources 1

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

  • SAE J2012Diagnostic Trouble Code Definitions (defines P0206 as a generic OBD-II code)

P0206 on Other Platforms

The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:

Which Vehicles Commonly Get DURAMAX-P0206?

  • 2001-2004 Chevy Silverado 2500/3500 HD 6.6L Duramax LB7
  • 2001-2004 GMC Sierra 2500/3500 HD 6.6L Duramax LB7
  • 2004.5-2005 Chevy Silverado 2500/3500 HD 6.6L Duramax LLY
  • 2004.5-2005 GMC Sierra 2500/3500 HD 6.6L Duramax LLY
  • 2006-2007 Chevy Silverado 2500/3500 HD 6.6L Duramax LBZ
  • 2006-2007 GMC Sierra 2500/3500 HD 6.6L Duramax LBZ
  • 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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