AutoCodes – GMC – P1242 GMC

P1242 GMC Code - Fuel Injector 7 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 7, Fuel Injector 7 harness is open or shorted, Fuel Injector 7 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: P1242 GMC indicates Fuel Injector 7 Control Circuit Shorted.
Common causes: Common causes include Faulty Fuel Injector 7, Fuel Injector 7 harness is open or shorted, Fuel Injector 7 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 1,278

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 P1242 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 P1242 GMC - Fuel Injector 7 Control Circuit Shorted - AutoCodes.com — P1242 GMC Code - Fuel Injector 7 Control Circuit Shorted

What does this mean?

What are the Possible Causes of the DTC P1242 GMC?

Faulty Fuel Injector 7
Fuel Injector 7 harness is open or shorted
Fuel Injector 7 circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P1242 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 P1242 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 P1242 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 P1242 GMC Code

1. What are the common symptoms of OBDII code P1242 GMC (Fuel Injector 7 Control Circuit Shorted)?

The common symptoms include rough idling, engine misfires, poor acceleration, and decreased fuel efficiency.

2. What are the possible causes of OBDII code P1242 GMC?

Possible causes of this code may include a short circuit in the wiring harness of fuel injector 7, a faulty fuel injector, or a problem with the Engine Control Module (ECM).

3. How can I diagnose the cause of OBDII code P1242 GMC?

To diagnose the cause, you can use a scan tool to check for the specific fault code, visually inspect the wiring harness and connectors, test the fuel injector for proper operation, and check the ECM for any issues.

4. Can I still drive my vehicle with OBDII code P1242 GMC?

It is not recommended to drive your vehicle with this code present, as it can lead to further damage to the engine and affect overall performance.

5. How can I repair OBDII code P1242 GMC?

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

6. Are there any DIY tips for fixing OBDII code P1242 GMC?

While some simple checks like inspecting the wiring harness and connectors can be done DIY, it is recommended to seek professional help for proper diagnosis and repair of this code.

7. Is it safe to reset the OBDII code P1242 GMC using a scan tool?

Resetting the code without addressing the underlying issue will not fix the problem. It is important to diagnose and repair the root cause before resetting the code.

8. How much does it cost to fix OBDII code P1242 GMC at a repair shop?

The cost of fixing this code can vary depending on the exact cause of the issue, but it may involve diagnostic fees, parts replacement costs, and labor charges.

9. Can a faulty fuel injector cause OBDII code P1242 GMC?

Yes, a faulty fuel injector can cause this code if it is shorted or not functioning properly, leading to a control circuit short.

10. How long does it typically take to repair OBDII code P1242 GMC?

The repair time can vary based on the complexity of the issue and the availability of parts, but it may take a few hours to a full day to diagnose and fix this code.