P0679: Cylinder 9 Glow Plug Circuit/Open
What to do
Driveable, with hard cold starting.
What this code means
A circuit fault on cylinder 9's glow plug, on large commercial and industrial diesels. Diagnosed as P0671.
Likely causes
Start here
- Failed glow plug · moderate
- Corroded or loose connector · easy
- Broken glow plug supply wire · moderate
Less common
- Failed glow plug control module · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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What makes one worth reading:
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