AutoCodes – GMC – U0077 2015 GMC Sierra

U0077 2015 GMC Sierra Code - Control Module Communication Chassis Expansion CAN Bus

Quick Answer

The devices connected to the chassis high speed General Motor Local Area Network (GMLAN) serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Check for more codes, Faulty Control Module, Control Module harness is open or shorted. 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 2015 GMC Sierra indicates Control Module Communication Chassis Expansion CAN Bus.
Common causes: Common causes include Check for more codes, Faulty Control Module, Control Module harness is open or shorted.
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 319

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 20, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U0077 2015 GMC Sierra Description

The devices connected to the chassis high speed General Motor Local Area Network (GMLAN) serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the devices when the ignition switch is in any position other than OFF. The chassis high speed GMLAN serial data bus uses terminating resistors that are in parallel with the chassis high speed GMLAN (+) and (-) circuits. The Diagnostic Trouble Code (DTC) sets when a supervised periodic message that includes the transmitter device availability has not been received.

OBDII Code U0077 2015 GMC Sierra - Control Module Communication Chassis Expansion CAN Bus - AutoCodes.com — U0077 2015 GMC Sierra Code - Control Module Communication Chassis Expansion CAN Bus

What does this mean?

What are the Possible Causes of the DTC U0077 2015 GMC Sierra?

Check for more codes
Faulty Control Module
Control Module harness is open or shorted
Control Module circuit poor electrical connection

How to Fix the DTC U0077 2015 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 U0077 2015 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 U0077 2015 GMC Sierra code?

Need more information on how to fix the U0077 2015 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the 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 U0077 2015 GMC Sierra Code

1. What does the OBDII code U0077 for a 2015 GMC Sierra mean?

The U0077 code indicates a communication problem in the Control Module Communication Chassis Expansion CAN Bus system.

2. What are the common symptoms of a U0077 code in a 2015 GMC Sierra?

Common symptoms include issues with the electronic stability control system, traction control system, and potentially the vehicle's steering system.

3. What are the possible causes of a U0077 code in a 2015 GMC Sierra?

Possible causes may include damaged wiring or connectors in the CAN Bus system, a faulty control module, or a software issue.

4. How can I diagnose a U0077 code in my 2015 GMC Sierra?

Diagnosis typically involves using a diagnostic scanner to retrieve the specific details of the code and then inspecting the CAN Bus system for any visible damage.

5. Can I still drive my 2015 GMC Sierra with a U0077 code present?

It is not recommended to drive the vehicle with a U0077 code present as it can affect the proper functioning of critical safety systems.

6. How can I repair a U0077 code in a 2015 GMC Sierra?

Repairing a U0077 code may involve repairing or replacing damaged wiring or connectors, reprogramming the control module, or replacing the faulty component causing the communication issue.

7. Is the U0077 code in a 2015 GMC Sierra easy to fix?

The complexity of fixing a U0077 code can vary depending on the exact cause, so it's best to consult a professional mechanic for an accurate diagnosis and repair.

8. Can a DIY enthusiast fix a U0077 code in a 2015 GMC Sierra?

While some basic troubleshooting steps can be taken by a DIY enthusiast, resolving a U0077 code may require advanced diagnostic equipment and expertise best handled by a professional.

9. Will resetting the U0077 code in my 2015 GMC Sierra make it go away permanently?

Simply resetting the code may temporarily clear the warning light, but if the underlying issue causing the U0077 code is not addressed, it is likely to return.

10. How much does it cost to repair a U0077 code in a 2015 GMC Sierra?

The cost of repairing a U0077 code can vary widely depending on the cause of the issue and the specific components that need to be repaired or replaced. It's best to get a professional diagnosis for an accurate estimate.