P129B 2014 GMC Sierra Code - Fuel Pump Driver Control Module System Voltage Low
Quick Answer
The Fuel Pump Power Control Module monitors the battery positive voltage circuit to verify the voltage is within the normal operating range. Common causes include Faulty Fuel Pump Driver Control Module, Fuel Pump Driver Control Module harness is open or shorted, Fuel Pump Driver Control Module 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
- P129B 2014 GMC Sierra indicates Fuel Pump Driver Control Module System Voltage Low.
- Common causes
- Common causes include Faulty Fuel Pump Driver Control Module, Fuel Pump Driver Control Module harness is open or shorted, Fuel Pump Driver Control Module 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 P129B 2014 GMC Sierra Description
What are the Possible Causes of the DTC P129B 2014 GMC Sierra?
- Faulty Fuel Pump Driver Control Module
- Fuel Pump Driver Control Module harness is open or shorted
- Fuel Pump Driver Control Module circuit poor electrical connection
How to Fix the DTC P129B 2014 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 P129B 2014 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 P129B 2014 GMC Sierra code?
Need more information on how to fix the P129B 2014 GMC Sierra code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P129B 2014 GMC Sierra code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P129B 2014 GMC Sierra Code
1. What does the OBDII code P129B mean on a 2014 GMC Sierra?
The P129B code indicates a low voltage issue in the Fuel Pump Driver Control Module (FPCM) system, which manages the fuel pump's operation.
2. What are the symptoms of the P129B code in a 2014 GMC Sierra?
Symptoms may include poor engine performance, difficulty starting the vehicle, stalling, reduced fuel efficiency, or the check engine light being illuminated.
3. What causes the P129B code to appear?
Common causes include a failing Fuel Pump Driver Control Module, wiring issues such as damaged or corroded connectors, a weak battery, or a faulty fuel pump.
4. Can a weak battery trigger the P129B code?
Yes, a weak or failing battery can cause a low voltage condition in the Fuel Pump Driver Control Module system, leading to the P129B code.
5. How do I diagnose the P129B code on a 2014 GMC Sierra?
Start by checking the battery voltage, inspecting all FPCM wiring and connectors for damage or corrosion, and testing the module itself for proper operation.
6. Can I drive my 2014 GMC Sierra with the P129B code?
While the vehicle may be drivable, it’s not recommended as the issue can lead to further engine performance problems or potential stalling.
7. How do I fix the P129B code on a GMC Sierra?
Repairs may include replacing the Fuel Pump Driver Control Module, repairing damaged wiring, cleaning corroded connectors, or replacing the fuel pump if necessary.
8. Is the Fuel Pump Driver Control Module expensive to replace?
The cost of replacement varies depending on parts and labor but typically ranges from $200 to $500.
9. Can a faulty fuel pump cause the P129B code?
Yes, a failing fuel pump can strain the Fuel Pump Driver Control Module and result in a low voltage issue.
10. Do I need to reprogram the Fuel Pump Driver Control Module after replacement?
In some cases, yes. Consult your vehicle’s repair manual or a qualified technician to determine if reprogramming is required for your specific model.
Discuss the causes and fixes for P129B 2014 GMC Sierra OBDII Code
Code P129B 2014 GMC Sierra comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
