AutoCodes – Ford – P066F Ford

P066F Ford Code - Cylinder 3 Glow Plug Control Circuit High

Quick Answer

The glow plug system is used to assist in providing the heat required to begin combustion during cold engine temperatures. Common causes include Faulty cylinder #3 glow plug, Cylinder #3 glow plug harness is open or shorted, Cylinder #3 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: P066F Ford indicates Cylinder 3 Glow Plug Control Circuit High.
Common causes: Common causes include Faulty cylinder #3 glow plug, Cylinder #3 glow plug harness is open or shorted, Cylinder #3 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.

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Code Popularity 1,771

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on May 08, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P066F Ford Description

The glow plug system is used to assist in providing the heat required to begin combustion during cold engine temperatures. The glow plugs are heated before and during cranking, as well as initial engine operation. The Engine Control Module (ECM) controls the glow plug ON times by monitoring coolant temperature and glow plug voltage. The California Glow Plug system has eight individual glow plug supply circuits between the controller and the glow plugs. If the feedback voltage from the controller to the ECM is not within range, the ECM sets the OBDII code.

OBDII Code P066F Ford - Cylinder 3 Glow Plug Control Circuit High - AutoCodes.com — P066F Ford Code - Cylinder 3 Glow Plug Control Circuit High

What does this mean?

What are the Possible Causes of the DTC P066F Ford?

Faulty cylinder #3 glow plug
Cylinder #3 glow plug harness is open or shorted
Cylinder #3 glow plug circuit poor electrical connection
Faulty glow plug module

How to Fix the DTC P066F Ford?

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 P066F Ford 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 P066F Ford code?

Need more information on how to fix the P066F Ford code? Get Access to Factory Service Manuals

Need Help with the Code?

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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 P066F Ford Code

1. What are the common symptoms of OBDII code P066F in a Ford, indicating a Cylinder 3 Glow Plug Control Circuit High issue?

The common symptoms include rough engine idle, reduced engine performance, and possible illumination of the check engine light.

2. What are the potential causes of the Cylinder 3 Glow Plug Control Circuit High code (P066F) in Ford vehicles?

Possible causes include a faulty glow plug in cylinder 3, damaged wiring or connectors in the glow plug circuit, or a malfunctioning glow plug control module.

3. How can I diagnose the Cylinder 3 Glow Plug Control Circuit High issue in my Ford when experiencing this OBDII code?

Diagnosis typically involves checking the glow plug in cylinder 3 for proper function, inspecting the wiring and connectors for any damage, and testing the glow plug control module for faults.

4. Can I continue driving my Ford with the P066F code related to the Cylinder 3 Glow Plug Control Circuit High issue?

It is not recommended to continue driving with this code unresolved, as it can lead to further engine problems and potential damage if left unattended.

5. Are there any DIY repair tips for addressing the P066F code in a Ford related to Cylinder 3 Glow Plug Control Circuit High?

DIY enthusiasts can start by inspecting the glow plug in cylinder 3, checking the wiring harness for any visible damage, and ensuring the connectors are securely attached.

6. How much does it typically cost to repair the Cylinder 3 Glow Plug Control Circuit High issue causing the P066F code in a Ford?

The cost of repair can vary depending on the exact cause of the issue, but it may involve replacing the faulty glow plug, repairing damaged wiring, or replacing the glow plug control module.

7. Is it necessary to visit a professional mechanic to resolve the P066F code related to the Cylinder 3 Glow Plug Control Circuit High issue in my Ford?

While some DIY repairs may be possible, consulting a professional mechanic is recommended for a thorough diagnosis and proper repair of the glow plug control circuit issue.

8. Can a faulty glow plug in cylinder 3 cause other problems besides triggering the P066F code in a Ford?

Yes, a faulty glow plug can lead to issues such as hard starting in cold weather, reduced fuel efficiency, and potential damage to the engine if not addressed promptly.

9. How long does it typically take to repair the Cylinder 3 Glow Plug Control Circuit High issue causing the P066F code in a Ford?

The repair time can vary based on the extent of the issue and the availability of parts, but it usually takes a few hours to a day to diagnose and fix the problem.

10. Is the Cylinder 3 Glow Plug Control Circuit High code (P066F) a common issue in Ford vehicles, or is it relatively rare?

While not as common as some other OBDII codes, the Cylinder 3 Glow Plug Control Circuit High issue can occur in Ford vehicles, especially in diesel engines with glow plug systems.