P06C9 GMC 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 GMC 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 GMC 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 GMC?
- 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 GMC?
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 GMC 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 GMC code?
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Information for Specific GMC Models
- P06C9 2014 GMC Sierra — Cylinder 5 Glow Plug Incorrect
- P06C9 2015 GMC Sierra — Cylinder 5 Glow Plug Incorrect
- P06C9 2016 GMC Sierra — Cylinder 5 Glow Plug Incorrect
- P06C9 2017 GMC Sierra — Cylinder 5 Glow Plug Incorrect
- P06C9 2018 GMC Sierra — Cylinder 5 Glow Plug Incorrect
Frequently Asked Questions about P06C9 GMC Code
What does the OBDII code P06C9 mean for a GMC vehicle?
The P06C9 code indicates that the cylinder 5 glow plug is not functioning correctly, which could affect cold starts and engine performance.
What are the common symptoms of the P06C9 code?
Symptoms may include difficulty starting in cold conditions, rough idling, reduced engine performance, and an illuminated check engine light.
What causes the P06C9 code to appear?
Common causes include a faulty glow plug, damaged wiring or connectors in the glow plug circuit, a malfunctioning glow plug control module, or a software issue in the engine control module (ECM).
Can I drive my GMC with the P06C9 code active?
While the vehicle may still be drivable, prolonged operation with this code could lead to inefficient cold starts, increased emissions, and potential damage to other engine components.
How do I diagnose the P06C9 code on a GMC?
Diagnosis involves using an OBDII scanner to confirm the code, visually inspecting the glow plug and its wiring, testing the glow plug with a multimeter, and checking the glow plug control module.
What is the most common fix for the P06C9 code?
The most common fix is replacing the faulty glow plug for cylinder 5. In some cases, repairing wiring or replacing the glow plug control module may also be necessary.
How much does it typically cost to repair the P06C9 code?
The repair cost can range from $100 to $300, depending on whether you only need a glow plug replacement or additional repairs like wiring fixes or module replacement.
Can a software issue cause the P06C9 code?
Yes, outdated or corrupted software in the ECM can sometimes trigger this code. Reflashing or updating the ECM may resolve the issue.
Will clearing the P06C9 code fix the problem?
Clearing the code will temporarily turn off the check engine light, but it won't resolve the underlying issue, and the code is likely to return.
How can I prevent the P06C9 code from reoccurring?
Regular maintenance, including inspecting glow plugs and wiring, and addressing engine issues promptly, can help prevent this code from recurring.
Discuss the causes and fixes for P06C9 GMC OBDII Code
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