P06C4 OBD II Trouble Code Cylinder 12 Glow Plug Circuit Range/Performance

How to quickly diagnose, repair, and info on symptoms and causes of a P06C4 code that indicates a detected range or performance problem with the cylinder #12 glow plug circuit.

Symptoms of P06C4 OBD II Trouble Code

  • Excessive black smoke from exhaust
  • Engine drivability issues
  • Delayed engine start up
  • Reduced fuel efficiency
  • Engine misfire codes may be stored

Common Causes of P06C4 OBD II Trouble Code

  • Bad glow plug(s)
  • Open or shorted glow plug control circuit
  • Loose or faulty glow plug connector
  • Defective glow plug timer

Severity of P06C4 OBD II Trouble Code

Any glow plug related code will likely be accompanied by drivability issues. A stored code P06C4 should be addressed with urgency.