P066F 2018 GMC Sierra Code - Cylinder 3 Glow Plug Control Circuit High Voltage
Quick Answer
The P066F diagnostic trouble code (DTC) for a 2018 GMC Sierra refers to an issue with the Cylinder 3 Glow Plug Control Circuit registering high voltage. Common causes include Faulty glow plug in Cylinder 3, Wiring issues in the glow plug control circuit, Corrosion or damage to the connectors related to the glow plug. 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
- P066F 2018 GMC Sierra indicates Cylinder 3 Glow Plug Control Circuit High Voltage.
- Common causes
- Common causes include Faulty glow plug in Cylinder 3, Wiring issues in the glow plug control circuit, Corrosion or damage to the connectors related to the glow plug.
- 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.
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Code P066F 2018 GMC Sierra Description
The P066F diagnostic trouble code (DTC) for a 2018 GMC Sierra refers to an issue with the Cylinder 3 Glow Plug Control Circuit registering high voltage. Glow plugs are crucial components in diesel engines, as they help with cold starting by heating the combustion chamber. When the control circuit for the glow plug in Cylinder 3 detects high voltage, it indicates a malfunction that can impact the engine's performance. This high voltage can disrupt the proper functioning of the glow plug, leading to difficulties in starting the engine, reduced fuel efficiency, and potential engine misfires. If left unaddressed, this issue could cause long-term damage to the engine and other related systems.
Common Causes of P066F 2018 GMC Sierra
- Faulty glow plug in Cylinder 3.
- Wiring issues in the glow plug control circuit.
- Corrosion or damage to the connectors related to the glow plug.
- Issues with the glow plug relay or control module.
- Electrical problems in the vehicle's system affecting the glow plug circuit.
Symptoms of P066F 2018 GMC Sierra
- Difficulty starting the engine, especially in cold weather.
- Reduced fuel efficiency.
- Engine misfires or rough idling.
- Illumination of the check engine light on the dashboard.
- Decreased overall engine performance.
How to Fix P066F 2018 GMC Sierra
- Begin by diagnosing the specific cause of the high voltage in the Cylinder 3 glow plug control circuit using a diagnostic scanner.
- Inspect the glow plug in Cylinder 3 for any signs of damage or malfunction and replace if necessary.
- Check the wiring and connectors in the glow plug circuit for any corrosion, loose connections, or damage, and repair or replace as needed.
- Test the glow plug relay and control module to ensure they are functioning correctly, replacing them if found to be faulty.
- Clear the DTC from the vehicle's computer system after completing the repairs and test the vehicle to ensure the issue has been resolved.
Cost to Fix P066F 2018 GMC Sierra
The cost of repairing a Cylinder 3 Glow Plug Control Circuit High Voltage issue in a 2018 GMC Sierra can vary depending on the specific cause of the problem and the labor rates in your area. On average, the parts for replacing a glow plug, relay, or control module can range from $50 to $200, while labor costs can be between $100 to $300. Overall, the total repair cost for this issue could fall in the range of $150 to $500. It's recommended to consult with a trusted mechanic or auto repair shop for a more accurate estimate based on your vehicle's specific needs.
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