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P0672MinorEngine

P0672: Cylinder 2 Glow Plug Circuit

3 vehicles · 3 makes · $200-$1,500 repair

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Most Reported On

2007-2025Mercedes-Benz SprinterSprinter 1500 +32001-2020Chevrolet Silverado 3500HD2007-2019GMC Sierra 3500HD

P0672 is an OBD-II diagnostic trouble code meaning “Cylinder 2 Glow Plug Circuit.” P0672 is a diesel-engine code indicating a fault in the glow plug circuit for cylinder number 2. Glow plugs heat the combustion chamber to help a diesel engine start, especially in cold weather, and the control module monitors each plug's circuit electrically. When it detects an open, short, or out-of-range condition on the cylinder 2 glow plug circuit, it sets this code. It generally causes hard cold starts, rough running until warm, and possibly white smoke on startup, while the check engine or glow plug light may illuminate. This code is most commonly reported on 2007-2025 Mercedes-Benz Sprinter (Sprinter 1500, Sprinter 2500, Sprinter 3500, Sprinter 4500), 2001-2020 Chevrolet Silverado 3500HD, and 2007-2019 GMC Sierra 3500HD, with repair costs ranging from $200 to $1,500.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (3)
  • Related Codes
  • FAQ
  • Sources (1)

Makes

  • Chevrolet1
  • GMC1
  • Mercedes-Benz1
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Common Causes

1Failed (open or shorted) glow plug on cylinder 2
2Corroded or loose glow plug connector/terminal
3Damaged or broken glow plug wiring/harness
4Faulty glow plug control module or relay
5High resistance/corrosion at the glow plug bus bar or strap
6Poor ground connection in the glow plug circuit
7Blown fuse feeding the glow plug circuit

Typical Repair Cost

$200 - $1,500

Based on 3 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P0672, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
Check Price on Amazon
Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
  • Repair Reports with verified fixes
  • Smog check readiness
  • Free app (iOS & Android)
Check Price on Amazon
Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
Check Price on Amazon
Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

  • All-system diagnostics (25+ modules)
  • Bi-directional control & active tests
  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
Check Price on Amazon

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (3)

Chevrolet P0672 page →
Silverado 3500HDModerate

Glow Plug Failure and Hard Cold Starting

2001-2020$200-$800250 reports
GMC P0672 page →
Sierra 3500HDModerate

Glow plug control module / glow plug circuit faults causing hard cold starts (Duramax)

2007-2019$250-$1,200110 reports
Mercedes-Benz P0672 page →
SprinterModerate

Glow Plug Failure and Cold Start Issues

2007-2025$300-$1,5001,500 reports

Related Codes (8)

P0670Glow Plug Module Control CircuitP0671Cylinder 1 Glow Plug CircuitP0673Cylinder 3 Glow Plug CircuitP0674Cylinder 4 Glow Plug Circuit002FManufacturer-Specific Diagnostic Code16566Mass Air Flow Sensor Signal Too Low (VAG)ECM-940AEngine Control Module Fault (Volvo)P0008Engine Position System Performance - Bank 1

FAQ

What does P0672 mean?

P0672 stands for "Cylinder 2 Glow Plug Circuit." P0672 is a diesel-engine code indicating a fault in the glow plug circuit for cylinder number 2. Glow plugs heat the combustion chamber to help a diesel engine start, especially in cold weather, and the control module monitors each plug's circuit electrically. When it detects an open, short, or out-of-range condition on the cylinder 2 glow plug circuit, it sets this code. It generally causes hard cold starts, rough running until warm, and possibly white smoke on startup, while the check engine or glow plug light may illuminate.

What are the most common causes of P0672?

The most common causes of P0672 are: Failed (open or shorted) glow plug on cylinder 2, Corroded or loose glow plug connector/terminal, Damaged or broken glow plug wiring/harness, Faulty glow plug control module or relay, High resistance/corrosion at the glow plug bus bar or strap, Poor ground connection in the glow plug circuit, Blown fuse feeding the glow plug circuit. The specific cause varies by vehicle.

How much does it cost to fix P0672?

Repair costs for P0672 range from $200 to $1,500, depending on the vehicle and root cause.

Which vehicles are affected by P0672?

Au7o has documented P0672 across 3 vehicle models from 3 manufacturers: Chevrolet, GMC, Mercedes-Benz.

Sources (1)

  • owner-reportr/MechanicAdvice search results for “P0670 Duramax glow plug module” – multiple owner posts about hard cold starts/extended cranking tied to glow plug control module and glow plug circuit DTCs

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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