P06BC
Cylinder 4 Glow Plug Circuit Range/Performance
Generic OBD-II
Real-world scan data
Seen in
39
scans in the past year
Found in
<0.1%
of scans
<0.1%
of scans that found faults
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 the glow plug wiring and connections for any loose or damaged wires.
- Test the glow plug relay to ensure it is functioning properly.
- Inspect the glow plugs for any signs of damage or failure, and replace if necessary.
- Verify proper voltage is reaching the glow plug circuit.
- If all else fails, consider replacing the engine control module (ECM) as it might be causing the issue.
Common causes
Most likely first
- Faulty glow plug in cylinder 4
- Wiring issue or loose connection in the glow plug circuit for cylinder 4
- Faulty glow plug control module or relay
How to diagnose & fix
Work through it in order
- Engine misfire or rough idle
- Difficulty starting the engine
- Decreased fuel efficiency
- Illumination of the check engine light
- Loss of power or acceleration
Read & clear P06BC yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.