Cylinder 3 Glow Plug Incorrect
The P06C7 code indicates that the Engine Control Module (ECM) has detected an incorrect glow plug in cylinder 3, meaning the glow plug's resistance or electrical characteristics do not match the expected values for the engine. This is common in diesel engines where glow plugs are used to aid cold starts. The ECM monitors each glow plug's current draw and resistance; if cylinder 3's glow plug deviates from specifications, the code sets. This can lead to hard starting, misfires, and increased emissions.
1. Most Common Causes
- Incorrect glow plug installed in cylinder 3 (wrong part number, voltage rating, or heat range)
- Faulty or internally damaged glow plug in cylinder 3 (abnormal resistance change)
- Damaged wiring or connectors in the cylinder 3 glow plug circuit (corrosion, high resistance, short circuit)
- Internal failure of the Glow Plug Control Module (GPCM)
- PCM/GPCM programming or update error
2. Symptoms You Will Notice
- Check Engine Light on
- Hard starting, especially in cold weather
- Rough idle or misfire on cylinder 3
- Reduced fuel economy
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect glow plug wiring and connector for cylinder 3 for damage or corrosion.
Step 3: Measure resistance of cylinder 3 glow plug; compare to manufacturer specs (typically 0.5-2 ohms).
Step 4: Swap glow plug with another cylinder and see if code follows; if so, replace glow plug.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with this code, as it can cause hard starting, misfires, and potential damage to the engine or catalytic converter. Have it diagnosed and repaired promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for a single glow plug replacement, including parts and labor. If wiring or ECM issues are found, costs may be higher.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.