AutoCodes – Chevrolet – P2635 2017 Chevrolet Silverado

P2635 2017 Chevrolet Silverado Code - Fuel Pump Flow Performance

Quick Answer

The Engine Control Module (ECM) supplies voltage to the fuel pump driver control module when the ECM detects that the ignition is on. Common causes include Faulty Fuel Pump, Fuel Pump harness is open or shorted, Fuel Pump 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: P2635 2017 Chevrolet Silverado indicates Fuel Pump Flow Performance.
Common causes: Common causes include Faulty Fuel Pump, Fuel Pump harness is open or shorted, Fuel Pump 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 1,730

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 Apr 14, 2023

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P2635 2017 Chevrolet Silverado Description

The Engine Control Module (ECM) supplies voltage to the fuel pump driver control module when the ECM detects that the ignition is on. The voltage from the ECM to the fuel pump driver control module remains active for 2 s unless the engine is in crank or run. While this voltage is being received, the fuel pump driver control module closes the ground switch of the fuel pump. The fuel pump driver control module maintains correct fuel pressure based on the information from the fuel pressure sensor and varies the pulse width modulated controlled current to the fuel pump.
The Diagnostic Trouble Code (DTC) will be set when the fuel pump driver control module detects a difference of ± 60 kPa (8.7 PSI) at 400 kPa (58 PSI) request or ±45 kPa (6.5 PSI) at 300 kPa (43.5 PSI) request between the desired fuel pressure and the actual fuel pressure for approximately 10 s.

OBDII Code P2635 2017 Chevrolet Silverado - Fuel Pump Flow Performance - AutoCodes.com — P2635 2017 Chevrolet Silverado Code - Fuel Pump Flow Performance

What does this mean?

What are the Possible Causes of the DTC P2635 2017 Chevrolet Silverado?

Faulty Fuel Pump
Fuel Pump harness is open or shorted
Fuel Pump circuit poor electrical connection
Faulty Fuel Pump Control Module (if applicable)

How to Fix the DTC P2635 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 does this mean?

Code Tech Notes

There is a Factory Service Bulletin for the following Chevrolet Models:

- 2014-2018 Chevrolet Silverado
- 2015-2018 Chevrolet Suburban
- 2015-2018 Chevrolet Tahoe

If the Diagnostic Trouble Codes (DTC) P2635, U0074, and/or U18A2 are set, it may be found that the actual fuel pressure (low-pressure system) will be reading substantially higher than desired fuel pressure, in this case, the cause of the problem is a loss of communication between Engine Control Module (ECM) and Fuel Pump Control Module (FPCM).

- Diagnose for any communication DTCs set (U0074 would take priority over U18A2 if both set) before addressing DTC P2635.
- If DTC P2635 is not resolved by correcting the communication DTCs, only then should diagnose the DTC P2635.
- It has been found that a communication issue between the FPCM and ECM can potentially induce DTC P2635 and result in a pressure differential between actual and desired fuel system pressures.
- If the actual fuel pressure is substantially higher than desired (10 psi / 70 kPa or more), replacement of the fuel pump control module or fuel system components typically will not resolve this issue.
- If the actual fuel pressure is substantially lower than desired (10 psi / 70 kPa or more), this Factory Service Bulletin would NOT apply. It would be recommended to diagnose low actual fuel pressure.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P2635 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 P2635 2017 Chevrolet Silverado code?

Need more information on how to fix the P2635 2017 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P2635 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 P2635 2017 Chevrolet Silverado Code

1. What are common symptoms of OBDII code P2635 in a 2017 Chevrolet Silverado related to fuel pump flow performance?

The common symptoms include poor engine performance, decreased fuel efficiency, rough idling, and potential stalling.

2. What are potential causes of the P2635 code in a 2017 Chevrolet Silverado?

Possible causes include a faulty fuel pump, clogged fuel filter, fuel pressure regulator issues, wiring problems, or a failing fuel pump control module.

3. How can I diagnose the P2635 code in my 2017 Chevrolet Silverado?

Diagnosing the code involves using an OBDII scanner to retrieve the code, checking the fuel pump pressure, inspecting the fuel pump and related components for damage or clogs, and testing the fuel pump control module.

4. Can a clogged fuel filter trigger the P2635 code in a 2017 Chevrolet Silverado?

Yes, a clogged fuel filter can restrict fuel flow and cause inadequate fuel pump performance, triggering the P2635 code.

5. What are some repair tips for fixing the P2635 code on a 2017 Chevrolet Silverado?

Repair tips include replacing a faulty fuel pump, cleaning or replacing a clogged fuel filter, checking and repairing any damaged wiring, and ensuring proper fuel pump control module function.

6. Are there any safety precautions to consider when working on the fuel system related to the P2635 code in a 2017 Chevrolet Silverado?

Yes, it is essential to disconnect the vehicle's battery before working on the fuel system to prevent any electrical mishaps. Additionally, handle fuel with caution and avoid smoking or creating sparks in the vicinity.

7. Can a DIY enthusiast fix the P2635 code issue in a 2017 Chevrolet Silverado?

While some aspects of diagnosing and repairing the P2635 code can be done by a DIY enthusiast, working on the fuel system may require specialized tools and expertise. It is recommended to consult a professional mechanic for complex fuel system repairs.

8. How urgent is it to address the P2635 code in a 2017 Chevrolet Silverado?

It is crucial to address the P2635 code promptly to prevent potential engine damage, poor performance, and safety hazards due to fuel system issues.

9. Is it necessary to clear the P2635 code after fixing the issue in a 2017 Chevrolet Silverado?

Yes, it is recommended to clear the code using an OBDII scanner after fixing the underlying problem. This ensures the vehicle's onboard computer registers the repair and resets the Check Engine Light.

10. Can extreme weather conditions affect the fuel pump flow performance related to the P2635 code in a 2017 Chevrolet Silverado?

Extreme weather conditions, such as very high or low temperatures, can impact fuel pump performance and exacerbate existing issues related to the P2635 code. Regular maintenance and monitoring are essential in such conditions.