P0629 Buick Code - Fuel Pump Speed Output Circuit High Voltage
Quick Answer
The P0629 diagnostic trouble code (DTC) for Buick vehicles refers to the Fuel Pump Speed Output Circuit High Voltage. Common causes include Malfunctioning fuel pump control module: The control module responsible for regulating the fuel pump speed may be faulty, causing the high voltage condition, Faulty fuel pump: A malfunctioning fuel pump can also trigger this code, as it may not be able to deliver the correct amount of fuel to the engine, Short circuit in the wiring: A short circuit in the wiring connected to the fuel pump speed output circuit can disrupt the voltage levels, leading to this issue. 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
- P0629 Buick indicates Fuel Pump Speed Output Circuit High Voltage.
- Common causes
- Common causes include Malfunctioning fuel pump control module: The control module responsible for regulating the fuel pump speed may be faulty, causing the high voltage condition, Faulty fuel pump: A malfunctioning fuel pump can also trigger this code, as it may not be able to deliver the correct amount of fuel to the engine, Short circuit in the wiring: A short circuit in the wiring connected to the fuel pump speed output circuit can disrupt the voltage levels, leading to this issue.
- 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.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code P0629 Buick Description
The P0629 diagnostic trouble code (DTC) for Buick vehicles refers to the Fuel Pump Speed Output Circuit High Voltage. This code indicates that there is a high voltage condition in the fuel pump speed output circuit. The fuel pump speed output circuit is responsible for controlling the speed of the fuel pump, which ensures that the correct amount of fuel is delivered to the engine for optimal performance. When this circuit is compromised, it can lead to various issues with the fuel delivery system, affecting the vehicle's overall performance.
Common Causes of P0629 Buick
- Malfunctioning fuel pump control module: The control module responsible for regulating the fuel pump speed may be faulty, causing the high voltage condition.
- Faulty fuel pump: A malfunctioning fuel pump can also trigger this code, as it may not be able to deliver the correct amount of fuel to the engine.
- Short circuit in the wiring: A short circuit in the wiring connected to the fuel pump speed output circuit can disrupt the voltage levels, leading to this issue.
- Problem with the fuel pump speed sensor: If the sensor that monitors the fuel pump speed is damaged or malfunctioning, it can cause a high voltage condition in the circuit.
Symptoms of P0629 Buick
- Poor fuel economy: The vehicle may experience a decrease in fuel efficiency due to improper fuel delivery.
- Engine stalling: The engine may stall unexpectedly, especially during acceleration or at higher speeds.
- Rough idling: The engine may idle unevenly or experience fluctuations in RPM.
- Difficulty starting: The vehicle may have trouble starting or may take longer to start than usual.
- Check engine light: The check engine light may illuminate on the dashboard, indicating a problem with the fuel pump speed output circuit.
How to Fix P0629 Buick
- Diagnose the issue: Use a diagnostic scanner to read the code and identify the specific cause of the high voltage condition in the fuel pump speed output circuit.
- Inspect the fuel pump control module: Check the fuel pump control module for any signs of damage or malfunction and replace it if necessary.
- Test the fuel pump: Verify the functionality of the fuel pump by conducting a fuel pressure test and replace it if it is found to be faulty.
- Check the wiring: Inspect the wiring connected to the fuel pump speed output circuit for any shorts or damage and repair or replace as needed.
- Replace the fuel pump speed sensor: If the fuel pump speed sensor is identified as the cause of the issue, replace it to restore proper functioning of the fuel pump speed output circuit.
Cost to Fix P0629 Buick
The typical repair costs for addressing a P0629 code in a Buick vehicle can range from $200 to $800, depending on the specific cause of the issue and the extent of the repairs needed. This estimate includes the cost of parts such as a new fuel pump control module, fuel pump, wiring, and sensor, as well as labor costs for diagnosis and repair. It's important to note that the actual cost may vary based on the location of the repair shop, the make and model of the vehicle, and the type of engine. Additionally, diagnostic time and labor rates can also impact the overall repair costs, with rates typically ranging from $80 to $150 per hour. For a more accurate estimate, it is recommended to consult with a local auto repair shop.
Need more information about the P0629 Buick code?
Need more information on how to fix the P0629 Buick code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P0629 Buick code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P0629 Buick Code
No Frequently Asked Questions about P0629 Buick Code found.
Discuss the causes and fixes for P0629 Buick OBDII Code
Code P0629 Buick 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.