P124B 2018 GMC Sierra Code - Injector 4 Positive Voltage Control Circuit Shorted to Control Circuit
Quick Answer
The Engine Control Module (ECM) supplies voltage to each fuel injector on the injector high voltage supply circuits. Common causes include Faulty Fuel Injector 4, Fuel Injector 4 harness is open or shorted, Fuel Injector 4 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
- P124B 2018 GMC Sierra indicates Injector 4 Positive Voltage Control Circuit Shorted to Control Circuit.
- Common causes
- Common causes include Faulty Fuel Injector 4, Fuel Injector 4 harness is open or shorted, Fuel Injector 4 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.
Code P124B 2018 GMC Sierra Description
What are the Possible Causes of the DTC P124B 2018 GMC Sierra?
- Faulty Fuel Injector 4
- Fuel Injector 4 harness is open or shorted
- Fuel Injector 4 circuit poor electrical connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P124B 2018 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 is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P124B 2018 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.
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Frequently Asked Questions about P124B 2018 GMC Sierra Code
1. What does the OBDII code P124B mean on a 2018 GMC Sierra?
P124B indicates that the Injector 4 Positive Voltage Control Circuit is shorted to its Control Circuit, preventing proper operation of injector 4.
2. What are the common symptoms of code P124B in a 2018 GMC Sierra?
Symptoms may include engine misfires, rough idling, reduced power, poor fuel efficiency, and the check engine light turning on.
3. What causes the P124B code to appear in a 2018 GMC Sierra?
Common causes include damaged wiring or connectors for injector 4, a faulty injector, short circuits, or issues with the Powertrain Control Module (PCM).
4. Can I drive my 2018 GMC Sierra with a P124B code?
Driving with this code is not recommended, as it may lead to poor engine performance, further damage to the injector system, or increased emissions.
5. How do I diagnose the P124B code in a 2018 GMC Sierra?
Start by inspecting the wiring and connectors for injector 4 for damage or corrosion. Use a multimeter to check for short circuits, and test the injector for proper operation.
6. How can I fix the P124B code on my 2018 GMC Sierra?
Repairs may include replacing damaged wiring, repairing corroded connectors, replacing injector 4, or reprogramming or replacing the PCM if it's determined to be faulty.
7. How much does it cost to repair a P124B code on a 2018 GMC Sierra?
Repair costs can vary depending on the issue. Injector replacements may cost $200-$500, while PCM repairs or replacements may cost $500-$1,200, excluding labor.
8. Can a bad fuel injector cause the P124B code in a 2018 GMC Sierra?
Yes, a faulty injector 4 can cause this code by disrupting the voltage or control circuit operation.
9. Does clearing the P124B code solve the problem in a 2018 GMC Sierra?
Clearing the code without addressing the underlying issue will not fix the problem, and the code will likely return.
10. What tools are needed to diagnose and fix the P124B code on a 2018 GMC Sierra?
You’ll need an OBDII scanner, a multimeter, and possibly wiring repair tools or an injector tester to diagnose and resolve the issue.
Discuss the causes and fixes for P124B 2018 GMC Sierra OBDII Code
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