DURAMAX-P0675 moderate Duramax ›

Cylinder 5 Glow Plug Circuit

The DURAMAX-P0675 (Duramax) diesel fault code means: Cylinder 5 Glow Plug Circuit. This is a moderate severity code.

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Keep driving?
Yes, but fix soon
DIY difficulty
intermediate
Estimated cost
$30-$80 per glow plug + labor; full set $250-$600
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What Are the Symptoms of DURAMAX-P0675?

  • Hard start in cold weather
  • White smoke at start-up
  • Rough idle until warm
  • Check Engine Light (may take one cold start to set)

What Causes DURAMAX-P0675? (Most Likely First)

  • Failed glow plug on cylinder 5 Very Likely
  • Glow plug controller / relay fault Likely
  • Broken glow plug tip — requires head removal (LLY/LBZ had 'swelled' glow plug failures) Possible
  • Open or damaged glow plug wire Possible

Can I Still Drive with DURAMAX-P0675?

Yes, but fix soon. DURAMAX-P0675 is rated moderate severity. It is not an immediate stop-driving fault, but it will not clear itself — book the repair rather than ignoring it.

Frequently Asked Questions

What is P0675 on a Duramax?

Duramax code P0675 (Cylinder 5 Glow Plug Circuit) is a moderate-severity diagnostic trouble code triggered by the engine control module when it detects a problem in the associated system. On LLY/LBZ engines, glow plugs can swell and break inside the head — always unscrew them slowly while monitoring torque.

Is a Duramax P0675 safe to drive?

Yes in warm weather. In cold weather, a failed glow plug makes cold starts difficult and increases engine wear.

How much does it cost to fix P0675 on a Duramax?

Individual glow plug replacement is $30-$80 parts, 1-2 hours labor. Many owners replace all 8 if multiple are failing.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose DURAMAX-P0675?

  1. Measure resistance across each glow plug — should be ~0.5-2 ohms, open = failed

  2. Command glow plug 'on' with scan tool and verify battery voltage at the plug tip

  3. Pull failed glow plug slowly — if it's swelled / broken, professional extraction may be required

  4. Replace glow plug with OEM or Motorcraft-equivalent; torque to 18 ft-lb

  5. Monitor for return after one or two cold starts to confirm repair

Sources 1

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

  • SAE J2012Diagnostic Trouble Code Definitions (defines P0675 as a generic OBD-II code)

P0675 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-P0675?

  • 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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