AutoCodes – GMC – P20BF 2016 GMC Sierra

P20BF 2016 GMC Sierra Code - Reductant Heater 2 Control Circuit Low Voltage

Quick Answer

As reductant will freeze at temperatures below -11°C (12°F), there are 2 reductant heaters located in the reductant tank. Common causes include Faulty Reductant Heater, Reductant Heater harness is open or shorted, Reductant Heater 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: P20BF 2016 GMC Sierra indicates Reductant Heater 2 Control Circuit Low Voltage.
Common causes: Common causes include Faulty Reductant Heater, Reductant Heater harness is open or shorted, Reductant Heater 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 228

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 29, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P20BF 2016 GMC Sierra Description

As reductant will freeze at temperatures below -11°C (12°F), there are 2 reductant heaters located in the reductant tank. One heats the reductant in the tank, and one heats the reductant supplied to the reductant injector supply pipe. The Engine Control Module (ECM) monitors the reductant temperature in the tank in order to determine if the reductant temperature is below its freeze point. If the ECM determines that the reductant may be frozen, it activates a "defrost strategy" energizing the reductant eater. This energizing action terminates when the temperature sensor measures a threshold value over which the heater must be deactivated.
The Diagnostic Trouble Code (DTC) will be set when the ECM indicates the reductant line heater control circuit is shorted to ground or overloaded for greater than 4 s.

OBDII Code P20BF 2016 GMC Sierra - Reductant Heater 2 Control Circuit Low Voltage - AutoCodes.com — P20BF 2016 GMC Sierra Code - Reductant Heater 2 Control Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P20BF 2016 GMC Sierra?

Faulty Reductant Heater
Reductant Heater harness is open or shorted
Reductant Heater circuit poor electrical connection
Faulty Reductant Pump and Sensor Assembly
Faulty Reductant Control Module

How to Fix the DTC P20BF 2016 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 P20BF 2016 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.

Need more information about the P20BF 2016 GMC Sierra code?

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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 P20BF 2016 GMC Sierra Code

1. What are the common symptoms of OBDII code P20BF in a 2016 GMC Sierra?

- Common symptoms include the Check Engine Light illuminating, reduced engine performance, and potential issues with the vehicle's emissions system.

2. What does the OBDII code P20BF "Reductant Heater 2 Control Circuit Low Voltage" indicate in a 2016 GMC Sierra?

- This code indicates a problem with the control circuit for the reductant heater 2, which is part of the vehicle's emissions system.

3. What are the possible causes of OBDII code P20BF in a 2016 GMC Sierra?

- Possible causes include a faulty reductant heater, damaged wiring or connectors related to the heater circuit, or issues with the vehicle's powertrain control module.

4. How can I diagnose the cause of OBDII code P20BF in my 2016 GMC Sierra?

- Diagnosing this code typically involves inspecting the reductant heater 2 circuit, checking for wiring issues, testing the heater's resistance, and verifying proper power supply to the heater.

5. Can I continue driving my 2016 GMC Sierra with OBDII code P20BF present?

- It is not recommended to continue driving with this code present, as it can lead to reduced engine performance and potential emissions system issues.

6. Is it safe to clear the OBDII code P20BF in a 2016 GMC Sierra without fixing the underlying issue?

- Clearing the code without addressing the underlying problem may temporarily turn off the Check Engine Light, but the issue will likely reoccur, affecting vehicle performance and emissions.

7. How much does it typically cost to repair OBDII code P20BF in a 2016 GMC Sierra?

- The cost of repairing this code can vary depending on the cause of the issue, but it may involve replacing the reductant heater, repairing wiring, or addressing other related components.

8. Can I repair OBDII code P20BF in my 2016 GMC Sierra myself, or do I need a professional mechanic?

- While some DIY enthusiasts may be able to diagnose and repair this code, it is recommended to consult a professional mechanic for accurate diagnosis and proper repair to ensure the issue is resolved correctly.

9. Are there any preventative maintenance tips to avoid OBDII code P20BF in a 2016 GMC Sierra?

- Regularly inspecting the emissions system components, keeping up with scheduled maintenance, and addressing any warning signs promptly can help prevent issues that may trigger this code.

10. How long does it take to repair OBDII code P20BF in a 2016 GMC Sierra?

- The repair time can vary based on the specific cause of the issue and the complexity of the repair needed, but it may take a few hours to a day to diagnose and fix the problem.