P129B 2017 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 2017 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 2017 GMC Sierra Description
What are the Possible Causes of the DTC P129B 2017 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 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 is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P129B 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.
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Frequently Asked Questions about P129B 2017 GMC Sierra Code
1. What does the OBDII code P129B mean on a 2017 GMC Sierra?
The P129B code indicates that the Fuel Pump Driver Control Module (FPCM) has detected a low system voltage condition.
2. What are the symptoms of the P129B code on a 2017 GMC Sierra?
Symptoms may include hard starting, engine stalling, reduced engine performance, or the illumination of the check engine light.
3. What causes the P129B code to appear on a 2017 GMC Sierra?
Common causes include a failing Fuel Pump Driver Control Module, poor electrical connections, corroded wiring, or a weak battery.
4. Can a weak battery trigger the P129B code?
Yes, a weak or failing battery can cause low voltage to the Fuel Pump Driver Control Module, triggering the P129B code.
5. How can I diagnose the P129B code on my 2017 GMC Sierra?
Start by checking the battery voltage and state of charge, inspect wiring and connectors to the FPCM, and test the FPCM for proper operation.
6. Is it safe to drive with the P129B code on a 2017 GMC Sierra?
Driving with this code is not recommended as it may lead to stalling or further damage to the fuel system.
7. How do I fix the P129B code on a 2017 GMC Sierra?
Repairs may include replacing the Fuel Pump Driver Control Module, repairing or replacing damaged wiring, or ensuring the battery and charging system are functioning properly.
8. How much does it cost to fix the P129B code on a 2017 GMC Sierra?
Repair costs can vary but typically range from $200 to $600, depending on whether the FPCM requires replacement or if wiring repairs are needed.
9. Can I reset the P129B code without fixing the problem?
While you can clear the code with an OBDII scanner, the issue will likely return if the underlying problem isn’t addressed.
10. How can I prevent the P129B code from occurring again?
Regularly inspect the electrical system, ensure the battery is in good condition, and address any wiring or connection issues promptly.
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