P06C9 2018 GMC Sierra Code - Cylinder 5 Glow Plug Incorrect
Quick Answer
n the diesel engine, air alone is compressed in the cylinder. Common causes include Faulty cylinder #1 glow plug, Cylinder #1 glow plug harness is open or shorted, Cylinder #1 glow plug circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P06C9 2018 GMC Sierra indicates Cylinder 5 Glow Plug Incorrect.
- Common causes
- Common causes include Faulty cylinder #1 glow plug, Cylinder #1 glow plug harness is open or shorted, Cylinder #1 glow plug circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P06C9 2018 GMC Sierra Description
Control of the glow plugs is accomplished by the glow plug control module. The nominal voltage for the glow plugs is 5.4 volts. When the ignition is turned On, the glow plug control module applies 7.2 V for 2.2 s, then 5.7 V for 0.8 s, and then 5.4 V until 1200°C (2192°F) is reached. The maximum voltage of the system is 10 V. While the engine is running the voltage will vary between 4.7 - 10 V when in closed loop control to maintain a glow plug temperature that ranges from 1150° - 1180°C (2102° - 2156°F). The temperature and the power consumption are controlled between the Engine Control Module (ECM) and the glow plug control module within a wide range to suit the engine's pre-heating requirements. Each glow plug is energized individually. This capability yields more optimum heat times for the glow plugs, thus pre - glow times can be kept to a minimum for a short wait to crank times and maximum glow plug durability. A Diagnostic Trouble Code (DTC) will be set if the Glow Plug resistance is not within a calibrated range.
What are the Possible Causes of the DTC P06C9 2018 GMC Sierra?
- Faulty cylinder #1 glow plug
- Cylinder #1 glow plug harness is open or shorted
- Cylinder #1 glow plug circuit poor electrical connection
- Faulty Glow Plug Control Module
How to Fix the DTC P06C9 2018 GMC Sierra?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P06C9 2018 GMC Sierra code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P06C9 2018 GMC Sierra code?
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Frequently Asked Questions about P06C9 2018 GMC Sierra Code
1. What does the OBD-II code P06C9 mean on a 2018 GMC Sierra?
The P06C9 code indicates that the Cylinder 5 glow plug is operating incorrectly, often due to a malfunction or electrical issue.
2. What are the common symptoms of the P06C9 code in a 2018 GMC Sierra?
Symptoms may include rough engine starts in cold weather, reduced fuel efficiency, and the check engine light illuminated.
3. What causes the P06C9 code on a GMC Sierra?
Common causes include a faulty glow plug, damaged wiring or connectors, or a malfunctioning glow plug control module.
4. Can I drive my 2018 GMC Sierra with the P06C9 code active?
While the vehicle may still be drivable, it may struggle to start in cold weather and could experience reduced performance. Prompt repairs are recommended.
5. How do I diagnose the P06C9 code in my GMC Sierra?
To diagnose, inspect the glow plug for Cylinder 5, check wiring and connectors for damage, and test the glow plug control circuit using a diagnostic tool.
6. How do I fix the P06C9 code on a 2018 GMC Sierra?
Repairs may involve replacing the Cylinder 5 glow plug, repairing damaged wiring, or replacing the glow plug control module if necessary.
7. How much does it cost to fix the P06C9 code on a GMC Sierra?
The repair cost varies but typically ranges from $100 to $300, depending on whether the glow plug or control module needs replacement.
8. Can a faulty glow plug cause other issues in my GMC Sierra?
Yes, a faulty glow plug can lead to harder cold starts, reduced engine efficiency, and increased emissions.
9. Is the P06C9 code specific to Cylinder 5 on the 2018 GMC Sierra?
Yes, the P06C9 code specifically refers to an issue with the glow plug in Cylinder 5.
10. Do I need special tools to fix the P06C9 code on my GMC Sierra?
You may need basic hand tools and an OBD-II diagnostic scanner to troubleshoot and replace the faulty part.
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