Engine-Codes.com
Engine-Codes – GMC – U0077 2016 GMC Sierra

U0077 2016 GMC Sierra Code - Control Module Communication Chassis Expansion CAN Bus

Quick Answer

The U0077 diagnostic trouble code (DTC) for a 2016 GMC Sierra indicates a problem with the Control Module Communication Chassis Expansion CAN Bus. Common causes include Faulty wiring or connectors in the CAN bus system, Corrosion or damage to the CAN bus network, Malfunctioning chassis control modules. 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
U0077 2016 GMC Sierra indicates Control Module Communication Chassis Expansion CAN Bus.
Common causes
Common causes include Faulty wiring or connectors in the CAN bus system, Corrosion or damage to the CAN bus network, Malfunctioning chassis control modules.
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.
What is this?
Table of contents Created and updated by William Orellana on Sep 07, 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 U0077 2016 GMC Sierra Description

The U0077 diagnostic trouble code (DTC) for a 2016 GMC Sierra indicates a problem with the Control Module Communication Chassis Expansion CAN Bus. In modern vehicles, various control modules communicate with each other over a Controller Area Network (CAN) bus system to share data and control functions. The Chassis Expansion CAN Bus specifically handles communication between the chassis control modules, such as the ABS (Antilock Braking System) module, traction control module, and others.

OBDII Code U0077 2016 GMC Sierra - Control Module Communication Chassis Expansion CAN Bus
U0077 2016 GMC Sierra Code - Control Module Communication Chassis Expansion CAN Bus

Common Causes of U0077 2016 GMC Sierra

  1. Faulty wiring or connectors in the CAN bus system.
  2. Corrosion or damage to the CAN bus network.
  3. Malfunctioning chassis control modules.
  4. Software issues within the control modules.
  5. Electrical interference from aftermarket accessories or modifications.

Symptoms of U0077 2016 GMC Sierra

  1. ABS warning light and traction control light illuminated on the dashboard.
  2. Loss of ABS functionality and traction control system.
  3. Unresponsive or erratic behavior of the electronic stability control system.
  4. Problems with the power steering system.
  5. Difficulty shifting gears in vehicles with automatic transmission.

How to Fix U0077 2016 GMC Sierra

  1. Begin by using a diagnostic scan tool to retrieve and record all fault codes present in the vehicle's system.
  2. Inspect the wiring harness and connectors associated with the Chassis Expansion CAN Bus for any signs of damage, corrosion, or loose connections.
  3. Test the communication lines within the CAN bus network to identify any faulty components or modules.
  4. Update the software of the affected control modules to the latest version provided by the manufacturer.
  5. Clear all fault codes after completing the repair process and perform a test drive to ensure the issue has been resolved.

Cost to Fix U0077 2016 GMC Sierra

The cost of repairing a U0077 code on a 2016 GMC Sierra can vary depending on the specific cause of the communication fault. On average, the repair cost for this issue can range from $200 to $500, including parts and labor. However, it's essential to note that diagnostic time and labor rates at auto repair shops can influence the final cost. Rates may vary based on the location, vehicle make and model, and the expertise of the technician. It's advisable to consult with a trusted mechanic or dealership to get a more accurate estimate for the repair.

Need more information about the U0077 2016 GMC Sierra code?

Need more information on how to fix the U0077 2016 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U0077 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 U0077 2016 GMC Sierra Code

1. What does the OBDII code U0077 mean on a 2016 GMC Sierra?

The U0077 code indicates a communication issue on the Chassis Expansion CAN Bus, which is part of the vehicle's control module network.

2. What are the common symptoms of code U0077 in a 2016 GMC Sierra?

Symptoms may include warning lights on the dashboard (e.g., ABS or traction control), loss of communication with certain modules, or intermittent electrical issues.

3. What causes the U0077 code to appear on a 2016 GMC Sierra?

Common causes include faulty wiring or connectors in the CAN Bus system, a defective control module, or interference from aftermarket devices.

4. How do I diagnose the U0077 code on my 2016 GMC Sierra?

Start by checking the CAN Bus wiring for damage or loose connections. Use a scan tool to verify communication between modules and inspect for other related trouble codes.

5. Can a bad control module cause the U0077 code?

Yes, a malfunctioning control module can disrupt communication on the CAN Bus and trigger the U0077 code.

6. Is it safe to drive a 2016 GMC Sierra with the U0077 code?

It may be possible to drive, but safety systems like ABS or stability control may not function correctly. It's best to repair the issue promptly.

7. How do I fix the U0077 code on my 2016 GMC Sierra?

Repairs may include fixing damaged wiring, reconnecting loose connectors, or replacing a faulty control module. A thorough diagnostic is essential.

8. Can aftermarket accessories cause the U0077 code?

Yes, improperly installed accessories can interfere with the CAN Bus system and cause communication errors like U0077.

9. How much does it cost to fix the U0077 code on a 2016 GMC Sierra?

Costs vary depending on the cause. Minor wiring repairs may cost $100-$300, while replacing a control module could range from $500 to $1,500.

10. Will clearing the U0077 code fix the problem?

Clearing the code may temporarily remove it, but the underlying issue must be resolved to prevent it from returning.

Discuss the causes and fixes for U0077 2016 GMC Sierra OBDII Code

Submit a New Comment

Code U0077 2016 GMC Sierra comments

No comments found for this page.