AutoCodes – GMC – P1239 GMC

P1239 GMC Code - Fuel Injector 6 Control Circuit Shorted

Quick Answer

The Engine Control Module (ECM) supplies voltage to each fuel injector on the injector positive voltage control circuits. Common causes include Faulty Fuel Injector 6, Fuel Injector 6 harness is open or shorted, Fuel Injector 6 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: P1239 GMC indicates Fuel Injector 6 Control Circuit Shorted.
Common causes: Common causes include Faulty Fuel Injector 6, Fuel Injector 6 harness is open or shorted, Fuel Injector 6 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 949

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 Nov 10, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1239 GMC Description

The Engine Control Module (ECM) supplies voltage to each fuel injector on the injector positive voltage control circuits. The ECM energizes each fuel injector by grounding the control circuit of that fuel injector. The ECM monitors the status of the injector positive voltage control circuits and the fuel injector control circuits. When a fuel injector circuit condition is detected by the ECM, the affected fuel injectors will be disabled and may disable the affected group of fuel injectors. The Diagnostic Trouble Code (DTC) will set when the ECM injector output driver detects an incorrect current on a fuel injector circuit.

OBDII Code P1239 GMC - Fuel Injector 6 Control Circuit Shorted - AutoCodes.com — P1239 GMC Code - Fuel Injector 6 Control Circuit Shorted

What does this mean?

What are the Possible Causes of the DTC P1239 GMC?

Faulty Fuel Injector 6
Fuel Injector 6 harness is open or shorted
Fuel Injector 6 circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P1239 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 P1239 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 P1239 GMC code?

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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 P1239 GMC Code

1. What are the common symptoms of OBDII code P1239 GMC (Fuel Injector 6 Control Circuit Shorted)?

The common symptoms include engine misfires, rough idling, reduced fuel efficiency, and the illumination of the Check Engine Light.

2. What are the possible causes of OBDII code P1239 GMC?

Possible causes of this code include a short circuit in the wiring connected to fuel injector 6, a faulty fuel injector, or issues with the Engine Control Module (ECM).

3. How can I diagnose the cause of OBDII code P1239 GMC?

Diagnosing the code typically involves inspecting the wiring harness for signs of damage, testing the fuel injector 6 for proper operation, and checking the ECM for any faults using a diagnostic scanner.

4. Can I still drive my vehicle with OBDII code P1239 GMC active?

It is not recommended to drive your vehicle with this code active, as it can lead to further damage to the engine and its components. It is best to address the issue promptly.

5. How can I repair OBDII code P1239 GMC?

Repairing this code may involve repairing or replacing the wiring harness connected to fuel injector 6, replacing the faulty fuel injector, or reprogramming the ECM if necessary.

6. Are there any DIY tips for addressing OBDII code P1239 GMC?

While diagnosing and repairing this code may require advanced knowledge and tools, you can start by checking the wiring harness for visible damage and ensuring all connections are secure before seeking professional help.

7. Is it safe to reset the Check Engine Light after fixing OBDII code P1239 GMC?

Once the underlying issue causing the code has been resolved, it is safe to reset the Check Engine Light using a diagnostic scanner to clear the error code.

8. How much does it cost to repair OBDII code P1239 GMC at a mechanic?

The cost of repairing this code can vary depending on the extent of the damage and the specific repairs needed. It is advisable to obtain quotes from different mechanics for an accurate estimate.

9. Can a faulty fuel injector cause OBDII code P1239 GMC?

Yes, a faulty fuel injector can cause this code to trigger, as it can lead to a short circuit in the control circuit connected to the injector, resulting in the ECM detecting the fault.

10. How long does it typically take to repair OBDII code P1239 GMC?

The repair time for this code can vary based on the complexity of the issue and the availability of parts. It is best to consult with a mechanic to get an estimate of the repair duration.