Glow Plug Control Module 1
What it means
P064C means the diesel glow-plug control module has a fault — the module that powers the glow plugs to preheat the cylinders for cold starting. The engine typically runs fine once warm, but cold starts can be difficult, rough, or produce white smoke until the glow-plug system is repaired.
Can I keep driving? The engine still runs once warm, but cold starts may be hard, rough, or smoky until it's fixed — get it checked, especially before cold weather.
Real-world scan data
Appears alongside · share of P064C scans
Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.
Common symptoms
What you'll notice
- Check-engine light, often with a glow-plug or wait-to-start light
- Hard starting when cold
- Rough running or white smoke on a cold start
- Reduced cold-weather performance
Common causes
Most likely first
- Faulty glow-plug control moduleLikely
- Damaged wiring or connectors at the moduleCommon
- Failed glow plug(s) loading the moduleCommon
- Faulty ECM (rare)Less often
How to diagnose & fix
Work through it in order
- Scan for companion glow-plug circuit codes.
- Check the control module's power, ground, and connectors.
- Measure each glow plug's resistance and replace any that read open.
- Replace the glow-plug control module if it fails its self-check.
- Clear the code and verify a normal cold start.
FAQ
Quick answers
Is it safe to drive with P064C?+
Can I just clear P064C?+
Related codes
Read & clear P064C yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.