P06C0
Cylinder 8 Glow Plug Circuit Range/Performance
Glow plug / diesel preheat
Generic OBD-II
High
What it means
P06C0 is a diesel code meaning the glow plug on cylinder 8 isn't performing within its expected electrical range — usually weak, high-resistance, or slow to heat. Glow plugs pre-heat the cylinder for cold starting, so the main symptoms are hard cold starts and rough, smoky running until the engine warms up.
High
Can I keep driving? You can usually drive once warm, but expect hard cold starts and rough cold running until the glow plug is repaired.
Common symptoms
What you'll notice
- Hard or slow starting when cold
- Rough idle and white smoke on a cold start until warm
- Glow plug (coil) warning light or check-engine light on
- Reduced power in cold weather
Common causes
Most likely first
- Weak or out-of-spec glow plug on cylinder 8Likely
- High-resistance wiring or a corroded connector to the glow plugCommon
- Poor glow plug groundCommon
- Faulty glow plug control moduleLess often
- Faulty ECM/PCM driver (less common)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and confirm the fault is on cylinder 8.
- Measure the cylinder 8 glow plug resistance and compare it to the others — replace it if it's out of range.
- Inspect the wiring and connector for added resistance and corrosion.
- Check the glow plug control module output and grounds.
- Repair the fault, clear the code, and retest a cold start.
FAQ
Quick answers
Is it safe to drive with P06C0?+
Usually yes once warm, but cold starts will be harder and it may run rough and smoke. It won't harm the engine, but fix it before cold weather.
Can I just clear P06C0?+
It returns once the ECM re-tests the glow plug. The weak plug or high-resistance wiring has to be repaired for the code to stay cleared.
Related codes
Often seen with P06C0
Read & clear P06C0 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX