AutoCodes – GMC – P1339 2017 GMC Sierra

P1339 2017 GMC Sierra Code - Cylinder 2 Glow Plug Offset Exceeded Learning Limit

Quick Answer

The Glow Plug Control Module has not learned the glow plug offset values. Common causes include Perform Glow Plug Learn procedure, Faulty Glow Plug 2, Glow Plug 2 harness is open or shorted. 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: P1339 2017 GMC Sierra indicates Cylinder 2 Glow Plug Offset Exceeded Learning Limit.
Common causes: Common causes include Perform Glow Plug Learn procedure, Faulty Glow Plug 2, Glow Plug 2 harness is open or shorted.
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 331

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Sep 30, 2022

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P1339 2017 GMC Sierra Description

The Glow Plug Control Module has not learned the glow plug offset values. If a glow plug has been replaced and the glow plug learn was not performed, or if the Glow Plug Control Module experiences an Electronically Erasable Programmable Read Only Memory (EEPROM) error or data corruption, this Diagnostic Trouble Code (DTC) to set. The DTC will be set if the glow plug hot resistance is outside a predefined threshold.

OBDII Code P1339 2017 GMC Sierra - Cylinder 2 Glow Plug Offset Exceeded Learning Limit - AutoCodes.com — P1339 2017 GMC Sierra Code - Cylinder 2 Glow Plug Offset Exceeded Learning Limit

What does this mean?

What are the Possible Causes of the DTC P1339 2017 GMC Sierra?

Perform Glow Plug Learn procedure
Faulty Glow Plug 2
Glow Plug 2 harness is open or shorted
Glow Plug 2 circuit poor electrical connection

How to Fix the DTC P1339 2017 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 does this mean?

Code Tech Notes

If a Glow Plug was replaced, perform a Glow Plug Learn procedure with a Scan Tool.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1339 2017 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 P1339 2017 GMC Sierra code?

Need more information on how to fix the P1339 2017 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1339 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 P1339 2017 GMC Sierra Code

1. What does the OBDII code P1339 mean on a 2017 GMC Sierra?

P1339 indicates that the Cylinder 2 Glow Plug Offset has exceeded its learning limit, meaning the glow plug system in that cylinder is not operating within the expected parameters.

2. What are the common symptoms of code P1339 on a GMC Sierra?

Symptoms may include a check engine light, difficulty starting in cold weather, reduced engine performance, or excessive exhaust smoke during startup.

3. What causes the P1339 code on a 2017 GMC Sierra?

Common causes include a faulty glow plug, poor electrical connection at the glow plug, a malfunctioning glow plug control module, or carbon buildup affecting the glow plug's performance.

4. Can I drive my GMC Sierra with the P1339 code active?

While the truck may still be drivable, driving with this code can lead to harder starts in cold weather and potentially damage other components over time. It's best to address the issue promptly.

5. How do I diagnose the P1339 code on a GMC Sierra?

Diagnosis typically involves checking the glow plug for cylinder 2, inspecting the wiring and connections, testing the glow plug control module, and possibly performing a resistance test on the glow plug.

6. How do I fix the P1339 code on a 2017 GMC Sierra?

Repairs may include replacing the cylinder 2 glow plug, cleaning carbon buildup, repairing or replacing damaged wiring, or replacing the glow plug control module if it's faulty.

7. How much does it cost to fix the P1339 code on a GMC Sierra?

The cost can vary, but replacing a glow plug typically ranges from $100 to $300, depending on labor rates and parts pricing. Additional repairs may increase the cost.

8. Can a bad glow plug cause other issues in the engine?

Yes, a faulty glow plug can cause cold starting problems, increased emissions, and potentially lead to incomplete combustion in the affected cylinder.

9. How can I prevent the P1339 code from returning on my GMC Sierra?

Regular maintenance, including inspecting the glow plug system and ensuring wiring and connections remain in good condition, can help prevent this issue.

10. Is the P1339 code specific to GMC vehicles?

No, the P1339 code can appear on other diesel vehicles as well, but the description and troubleshooting steps may vary based on the manufacturer.