OBD Guide

P0679

Cylinder 9 Glow Plug Circuit/Open

P0679 is an OBD-II diagnostic trouble code meaning: Cylinder 9 Glow Plug Circuit/Open. Common causes: burnt out glow plug cylinder 9, broken power wire. Estimated repair cost: $22–67.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$22–67 (est.)

Symptoms

  • Difficulty starting a multi-cylinder diesel engine in cold weather
  • Check Engine Light
  • White smoke on cold start
  • Unstable engine operation after starting
  • Glow plug indicator

Causes

  • Burnt out glow plug cylinder 9
  • Broken power wire
  • Oxidation or damage to the connector
  • GPCM module malfunction
  • Wiring damage

How to Fix

  1. Read OBD-II error codes
  2. Measure the resistance of the spark plug of cylinder 9 (standard: 0.5–2 Ohm)
  3. Inspect the wiring and connector
  4. Check supply voltage
  5. Replace a faulty glow plug
  6. If the error occurs again - GPCM diagnostics

Related codes

Error P0679 by Vehicle Brand

FAQ

What does the P0679 code mean?

P0679 is an OBD-II diagnostic trouble code that indicates: Cylinder 9 Glow Plug Circuit/Open

What causes a P0679 error code?

The most common causes of P0679 include: Burnt out glow plug cylinder 9; Broken power wire; Oxidation or damage to the connector; GPCM module malfunction.

How do I fix a P0679 diagnostic trouble code?

To fix P0679: Read OBD-II error codes. Measure the resistance of the spark plug of cylinder 9 (standard: 0.5–2 Ohm). Inspect the wiring and connector. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P0679?

Yes, but get it checked soon

How much does it cost to fix P0679?

The estimated repair cost for P0679 is $22–67. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat