AutoCodes – Chevrolet – P129C 2017 Chevrolet Silverado

P129C 2017 Chevrolet Silverado Code - Fuel Pump Driver Control Module System Voltage High

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: P129C 2017 Chevrolet Silverado indicates Fuel Pump Driver Control Module System Voltage High.
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.

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Code Popularity 255

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 Jul 04, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P129C 2017 Chevrolet Silverado Description

The Fuel Pump Power Control Module monitors the battery positive voltage circuit to verify the voltage is within the normal operating range. The Diagnostic Trouble Code (DTC) will be set when the Fuel Pump Driver Control Module detects the battery positive voltage is greater than 18 V for 1 s.

OBDII Code P129C 2017 Chevrolet Silverado - Fuel Pump Driver Control Module System Voltage High - AutoCodes.com — P129C 2017 Chevrolet Silverado Code - Fuel Pump Driver Control Module System Voltage High

What does this mean?

What are the Possible Causes of the DTC P129C 2017 Chevrolet Silverado?

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 P129C 2017 Chevrolet Silverado?

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 P129C 2017 Chevrolet Silverado 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 P129C 2017 Chevrolet Silverado code?

Need more information on how to fix the P129C 2017 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P129C 2017 Chevrolet Silverado code diagnosed by a professional: Find a repair shop in your area

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 P129C 2017 Chevrolet Silverado Code

1. What does the OBDII code P129C mean on a 2017 Chevrolet Silverado?

P129C indicates that the Fuel Pump Driver Control Module (FPCM) has detected a system voltage higher than the expected range.

2. What are the symptoms of code P129C in a 2017 Chevrolet Silverado?

Symptoms may include difficulty starting, reduced engine performance, stalling, or an illuminated check engine light.

3. What causes the P129C code to appear in a 2017 Chevrolet Silverado?

Common causes include a faulty Fuel Pump Driver Control Module, wiring issues (like damaged or corroded connectors), or a malfunctioning alternator causing excessive voltage.

4. Can a bad battery trigger the P129C code?

Yes, a failing battery or loose battery connections can cause voltage irregularities that trigger this code.

5. How is the P129C code diagnosed?

A mechanic typically inspects the FPCM, checks the wiring and connectors for damage, and tests the electrical system for excessive voltage output.

6. Can I drive my 2017 Chevrolet Silverado with the P129C code?

Driving with this code is not recommended, as it can lead to further electrical issues or damage to the fuel system.

7. How do you fix the P129C code on a 2017 Chevrolet Silverado?

Fixes may involve replacing the FPCM, repairing damaged wiring or connectors, or addressing issues with the alternator or battery.

8. How much does it cost to repair the P129C code?

Repair costs can vary but typically range from $200 to $600, depending on whether the FPCM, wiring, or another component needs replacement.

9. Can a faulty alternator cause the P129C code?

Yes, a malfunctioning alternator that produces excessive voltage can contribute to triggering this code.

10. Is the P129C code covered under warranty for a 2017 Chevrolet Silverado?

It depends on the warranty type and coverage. If your vehicle is under a powertrain or emissions warranty, the repair may be covered. Check with your dealer.