Engine-CodesGMC – P066B 2017 GMC Sierra

P066B 2017 GMC Sierra Code - Cylinder 1 Glow Plug Control Circuit High Voltage

Quick Answer

The P066B diagnostic trouble code (DTC) for a 2017 GMC Sierra indicates an issue with the Cylinder 1 Glow Plug Control Circuit High Voltage. Common causes include Faulty glow plug in Cylinder 1, Damaged wiring or connectors in the glow plug control circuit, Malfunctioning glow plug control module. 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
P066B 2017 GMC Sierra indicates Cylinder 1 Glow Plug Control Circuit High Voltage.
Common causes
Common causes include Faulty glow plug in Cylinder 1, Damaged wiring or connectors in the glow plug control circuit, Malfunctioning glow plug control module.
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.
Table of contents Created and updated by William Orellana on Sep 17, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P066B 2017 GMC Sierra Description

The P066B diagnostic trouble code (DTC) for a 2017 GMC Sierra indicates an issue with the Cylinder 1 Glow Plug Control Circuit High Voltage. Glow plugs are essential components in diesel engines that help with cold starts by heating the combustion chamber. When the engine is cold, the glow plug control module sends a signal to the glow plugs to heat up, ensuring proper combustion. In this case, the high voltage in the control circuit for Cylinder 1 indicates a potential malfunction in the glow plug system.

OBDII Code P066B 2017 GMC Sierra - Cylinder 1 Glow Plug Control Circuit High Voltage
P066B 2017 GMC Sierra Code - Cylinder 1 Glow Plug Control Circuit High Voltage

Common Causes of P066B 2017 GMC Sierra

  1. Faulty glow plug in Cylinder 1
  2. Damaged wiring or connectors in the glow plug control circuit
  3. Malfunctioning glow plug control module
  4. Electrical issues in the vehicle's system
  5. Corrosion or poor connections in the glow plug system

Symptoms of P066B 2017 GMC Sierra

  1. Difficulty starting the engine, especially in cold weather
  2. Rough idling or misfires
  3. Decreased fuel efficiency
  4. Illumination of the Check Engine Light
  5. Potential engine damage over time if left unresolved

How to Fix P066B 2017 GMC Sierra

  1. Begin by diagnosing the specific cause of the high voltage in the Cylinder 1 glow plug control circuit using a diagnostic scanner.
  2. Inspect the glow plug in Cylinder 1 for any signs of damage or malfunction and replace if necessary.
  3. Check the wiring and connectors in the control circuit for any corrosion, breaks, or loose connections, repairing or replacing them as needed.
  4. Test the glow plug control module for proper function and replace if it is found to be faulty.
  5. Clear the DTC and test the vehicle to ensure the issue has been resolved and that the glow plug system is operating correctly.

Cost to Fix P066B 2017 GMC Sierra

The typical repair costs for addressing a Cylinder 1 Glow Plug Control Circuit High Voltage issue can vary depending on the specific cause of the problem and the parts and labor required. In general, replacing a glow plug can cost between $50 to $150 per plug, while addressing wiring or connector issues may range from $100 to $300. The cost of a glow plug control module replacement can be around $150 to $400. Overall, the total repair cost for this issue could range from $200 to $800, including parts and labor.

Need more information about the P066B 2017 GMC Sierra code?

Need more information on how to fix the P066B 2017 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P066B 2017 GMC Sierra code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P066B 2017 GMC Sierra Code

No Frequently Asked Questions about P066B 2017 GMC Sierra Code found.

Discuss the causes and fixes for P066B 2017 GMC Sierra OBDII Code

Code P066B 2017 GMC Sierra comments

No comments found for this page.