Engine-CodesGMC – P0641 2016 GMC Sierra

P0641 2016 GMC Sierra Code - 5 Volt Reference 1 Circuit

Quick Answer

The P0641 code in a 2016 GMC Sierra relates to the 5 Volt Reference 1 Circuit. Common causes include Faulty 5-Volt Reference Circuit: The circuit itself may be damaged or have a short circuit, causing the voltage to drop or fluctuate, Sensor Malfunction: A faulty sensor connected to the 5-volt reference circuit can also trigger the P0641 code, Wiring Issues: Corrosion, fraying, or damage to the wiring harness connected to the 5-volt reference circuit can disrupt the voltage supply. 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
P0641 2016 GMC Sierra indicates 5 Volt Reference 1 Circuit.
Common causes
Common causes include Faulty 5-Volt Reference Circuit: The circuit itself may be damaged or have a short circuit, causing the voltage to drop or fluctuate, Sensor Malfunction: A faulty sensor connected to the 5-volt reference circuit can also trigger the P0641 code, Wiring Issues: Corrosion, fraying, or damage to the wiring harness connected to the 5-volt reference circuit can disrupt the voltage supply.
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.
Table of contents Created and updated by William Orellana on Sep 06, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0641 2016 GMC Sierra Description

The P0641 code in a 2016 GMC Sierra relates to the 5 Volt Reference 1 Circuit. This code indicates that there is a potential issue with the 5-volt reference circuit that supplies voltage to various sensors and components in the vehicle. The 5-volt reference voltage is crucial for the proper functioning of sensors such as the throttle position sensor, mass airflow sensor, and others. When this circuit malfunctions, it can lead to incorrect sensor readings, causing drivability issues and affecting overall performance.

OBDII Code P0641 2016 GMC Sierra - 5 Volt Reference 1 Circuit
P0641 2016 GMC Sierra Code - 5 Volt Reference 1 Circuit

Common Causes of P0641 2016 GMC Sierra

  1. Faulty 5-Volt Reference Circuit: The circuit itself may be damaged or have a short circuit, causing the voltage to drop or fluctuate.
  2. Sensor Malfunction: A faulty sensor connected to the 5-volt reference circuit can also trigger the P0641 code.
  3. Wiring Issues: Corrosion, fraying, or damage to the wiring harness connected to the 5-volt reference circuit can disrupt the voltage supply.
  4. PCM Failure: A malfunctioning Powertrain Control Module (PCM) can also be a potential cause of the code.

Symptoms of P0641 2016 GMC Sierra

  1. Check Engine Light: The most common symptom associated with the P0641 code is the illumination of the check engine light on the dashboard.
  2. Erratic Engine Performance: The vehicle may experience rough idling, stalling, or hesitation during acceleration due to incorrect sensor readings.
  3. Decreased Fuel Efficiency: A malfunctioning 5-volt reference circuit can lead to poor fuel economy as the engine may not be operating at its optimal efficiency.
  4. Inaccurate Gauge Readings: The vehicle's gauges, such as the speedometer or temperature gauge, may display incorrect readings due to sensor issues.

How to Fix P0641 2016 GMC Sierra

  1. Diagnose the Issue: Use a diagnostic scanner to read the code and perform tests to pinpoint the exact cause of the problem.
  2. Inspect Wiring: Check for any visible damage to the wiring harness and repair or replace as needed.
  3. Test Sensors: Test the sensors connected to the 5-volt reference circuit to identify any faulty components.
  4. Replace Components: Replace any damaged sensors or the PCM if necessary to restore proper voltage supply.
  5. Clear Codes: After completing the repairs, clear the diagnostic trouble codes and test drive the vehicle to ensure the issue has been resolved.

Cost to Fix P0641 2016 GMC Sierra

The cost of repairing a P0641 code can vary depending on the specific cause of the issue and the labor rates in your area. On average, the repair cost for this type of issue can range from $100 to $500, including parts and labor. It is advisable to consult with a professional mechanic to get an accurate estimate based on your vehicle's make and model. Additional diagnostic time and labor rates should also be considered when budgeting for this repair.

Tech Notes for P0641 2016 GMC Sierra

Disconnecting one component at a time from the affected 5 Volt reference circuit while observing the scan tool 5 Volt Reference Circuit Status parameter may help locate the fault. The scan tool parameter will change from Malfunction to OK when the source of the fault is disconnected. If all 5 Volt reference components have been disconnected and a fault is still indicated, the fault may exist in the wiring harness.

The 5 Volt reference 1 circuit provides 5 Volt to the following sensors: (Some models may have different sensors, please consult the factory service manual for the list of sensors for your model and year)

- Air conditioning (A/C) refrigerant pressure sensor
- Camshaft position sensor
- Engine oil pressure sensor
- Fuel pressure sensor
- Fuel rail pressure sensor
- Fuel tank pressure sensor
- Multifunction intake air sensor

Need more information about the P0641 2016 GMC Sierra code?

Need more information on how to fix the P0641 2016 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0641 2016 GMC Sierra 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 P0641 2016 GMC Sierra Code

No Frequently Asked Questions about P0641 2016 GMC Sierra Code found.

Discuss the causes and fixes for P0641 2016 GMC Sierra OBDII Code

Code P0641 2016 GMC Sierra comments

No comments found for this page.