Obdaryn

P06BACylinder 2 Glow Plug Circuit Range/Performance

  • Generic OBD-II code · Powertrain
  • Turns on the check-engine light
  • Matters for the ITP
  • Needs a drive cycle to confirm a fix
How the car detects it
The glow module calculates each plug's resistance from voltage and current while glowing. 'Range/performance' means the circuit is electrically intact but the resistance or current lies outside the specified window – typically an aged, high-resistance or wrong plug or contact resistance at the connector. CARB requires a single plug outside specification to be detected from model year 2010. Ford's 2023 6.7 L/3.0 L Power Stroke runs this check during heating after the open and short checks and flags a circuit above 2 Ω after about 3 s. GM does not use this code family. Ram's 6.7 L Cummins (from model year 2025, with glow plugs instead of the grid heater) set these codes falsely; the fix was reprogramming the engine module. On the 2014–15 Ram ProMaster 3.0 L diesel, plugs without an inner O-ring caused it; all plugs were replaced. P06BA concerns the glow plug of cylinder 2 alone; the same plug's open circuit is P0672, its control circuit low and high P066C/P066D, and an incorrect plug fitted P06C6.
What you may notice
  • Check engine and glow plug lamp
  • Harder cold start in frost
  • Rough running and white smoke after a cold start
  • Often no symptom when warm
Likely causes
  • LikelyGlow plug cylinder 2 aged or high-resistance
  • PossibleContact resistance at plug connector or terminal nut
  • PossibleWrong plug type or a plug with a manufacturing fault
  • RareEngine or glow module software (Ram 6.7 L from 2025)
Inspection (ITP)
Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
Repair
Medium · Often possible to do yourself.Typical cost: €50 – €500

Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.