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. No manufacturer document available to us uses this code for cylinders 9 and above; the description follows cylinders 1–8.
Low severity. Can I keep driving?You can keep driving, although cold starts will be harder. Avoid cranking the starter repeatedly on cold days.
Cylinder 10 is numbered according to the manufacturer: check your engine's manual before working on it.
Symptoms
- 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
Most likely causes
- Glow plug cylinder 10 aged or high-resistance
- Contact resistance at plug connector or terminal nut
- Wrong plug type or a plug with a manufacturing fault
- Engine or glow module software (Ram 6.7 L from 2025)
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
- It affects emissions.
What each character of P06C2 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 6: Control modules and outputs
- C2: Specific fault in that system
Frequently asked questions
Can I keep driving with code P06C2?
You can keep driving, although cold starts will be harder. Avoid cranking the starter repeatedly on cold days.
What causes code P06C2?
The most common causes are: glow plug cylinder 10 aged or high-resistance; contact resistance at plug connector or terminal nut; wrong plug type or a plug with a manufacturing fault.
Related codes
- P0680Cylinder 10 Glow Plug Circuit/Open
- P069CCylinder 10 Glow Plug Control Circuit Low
- P069DCylinder 10 Glow Plug Control Circuit High
- P06CECylinder 10 Glow Plug Incorrect
- P0670Glow Plug Control Module 1 Control Circuit/Open
- P052FGlow Plug Control Module 1 System Voltage
Sources
- law.cornell.edu: 13 CCR 1968.2
- techtips.ie: glow plugs
- fordservicecontent.com: obd summary diesel 2023
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.