AutoCodes – GMC – B1020 2017 GMC Sierra

B1020 2017 GMC Sierra Code - Auxiliary Electronic Control Unit Performance

Quick Answer

The Heating, Ventilation, and Air Conditioning (HVAC) module communicates with the HVAC controls via serial data. Common causes include Faulty Heating, Ventilation, and Air Conditioning (HVAC) Controls, HVAC Controls harness is open or shorted, HVAC Controls 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: B1020 2017 GMC Sierra indicates Auxiliary Electronic Control Unit Performance.
Common causes: Common causes include Faulty Heating, Ventilation, and Air Conditioning (HVAC) Controls, HVAC Controls harness is open or shorted, HVAC Controls 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 173

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 06, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1020 2017 GMC Sierra Description

The Heating, Ventilation, and Air Conditioning (HVAC) module communicates with the HVAC controls via serial data. This Diagnostic Trouble Code (DTC) indicates a fault in the HVAC controls. The HVAC controls may continue to respond normally to faceplate functions when this DTC is set. The DTC will be set when the HVAC module receives an improper status response indicating an internal ECU fault in the HVAC controls.

OBDII Code B1020 2017 GMC Sierra - Auxiliary Electronic Control Unit Performance - AutoCodes.com — B1020 2017 GMC Sierra Code - Auxiliary Electronic Control Unit Performance

What does this mean?

What are the Possible Causes of the DTC B1020 2017 GMC Sierra?

Faulty Heating, Ventilation, and Air Conditioning (HVAC) Controls
HVAC Controls harness is open or shorted
HVAC Controls circuit poor electrical connection

How to Fix the DTC B1020 2017 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 B1020 2017 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 B1020 2017 GMC Sierra code?

Need more information on how to fix the B1020 2017 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1020 2017 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 B1020 2017 GMC Sierra Code

1. What are the common symptoms of OBDII code B1020 in a 2017 GMC Sierra related to the Auxiliary Electronic Control Unit performance?

- Common symptoms include poor vehicle performance, rough idling, and issues with electronic accessories.

2. What are the possible causes of OBDII code B1020 in a 2017 GMC Sierra?

- The code B1020 may be triggered by a faulty Auxiliary Electronic Control Unit, damaged wiring, or loose connections.

3. How can I diagnose the issue causing OBDII code B1020 in my 2017 GMC Sierra?

- To diagnose the issue, you can use an OBDII scanner to read the specific fault codes and conduct a thorough inspection of the Auxiliary Electronic Control Unit and related wiring.

4. Can I continue driving my 2017 GMC Sierra with OBDII code B1020 present?

- It is not recommended to continue driving the vehicle with code B1020 present, as it can lead to further damage and potential safety hazards.

5. What are some repair tips for fixing OBDII code B1020 in a 2017 GMC Sierra?

- Repair tips may include checking and repairing any damaged wiring, ensuring proper connections, and, if needed, replacing the Auxiliary Electronic Control Unit.

6. Is it possible to reset OBDII code B1020 in a 2017 GMC Sierra without fixing the underlying issue?

- While you can clear the code temporarily, it will likely reappear until the underlying issue causing the code is fixed.

7. How much does it typically cost to repair OBDII code B1020 in a 2017 GMC Sierra?

- The cost of repair can vary depending on the exact cause of the code, but it may involve labor costs for diagnosis and replacement parts if needed.

8. Can a DIY enthusiast fix OBDII code B1020 in a 2017 GMC Sierra, or should it be done by a professional?

- Depending on your mechanical skills and knowledge, some DIY enthusiasts may be able to diagnose and repair the issue, but it is recommended to seek professional help for accurate diagnosis and repair.

9. Are there any recalls or technical service bulletins related to OBDII code B1020 in a 2017 GMC Sierra?

- It's recommended to check with GMC or the National Highway Traffic Safety Administration (NHTSA) for any recalls or technical service bulletins related to code B1020 in your specific vehicle.

10. How can regular maintenance help prevent OBDII code B1020 from occurring in a 2017 GMC Sierra?

- Regular maintenance, including inspections of electronic components and wiring, can help detect and address potential issues before they trigger OBDII code B1020.