U0077 2017 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 2017 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.
Code U0077 2017 GMC Sierra Description
What are the Possible Causes of the DTC U0077 2017 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 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 U0077 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.
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Frequently Asked Questions about U0077 2017 GMC Sierra Code
1. What does OBDII code U0077 mean on a 2017 GMC Sierra?
Code U0077 indicates a communication issue on the Chassis Expansion CAN (Controller Area Network) Bus, where modules are unable to communicate properly.
2. What are the common symptoms of code U0077 in a 2017 GMC Sierra?
Symptoms may include warning lights on the dashboard, malfunctioning electronic components (such as ABS or traction control), and intermittent or complete loss of communication with certain modules.
3. What causes the U0077 code on a GMC Sierra?
Common causes include a damaged or disconnected CAN Bus wiring, a faulty control module, corrosion in connectors, or a shorted circuit in the CAN Bus system.
4. Can a weak battery cause the U0077 code in a 2017 GMC Sierra?
Yes, a weak or failing battery can lead to insufficient voltage for proper CAN Bus communication, potentially triggering the U0077 code.
5. How can I diagnose the U0077 code on my 2017 GMC Sierra?
Start by inspecting the CAN Bus wiring and connectors for damage or corrosion, check the battery voltage, and use a scan tool to identify which module is not communicating.
6. Is it safe to drive my 2017 GMC Sierra with the U0077 code?
Driving with this code may impact the functionality of critical systems like ABS or traction control, so it is not recommended until the issue is resolved.
7. How do I fix the U0077 code on a 2017 GMC Sierra?
Repairs may include repairing or replacing damaged wiring or connectors, cleaning corroded connectors, or replacing a faulty control module.
8. Can clearing the U0077 code with a scan tool fix the problem?
Clearing the code may temporarily remove the warning, but it won’t fix the underlying communication issue. Proper diagnosis and repair are necessary.
9. How much does it cost to repair the U0077 code on a GMC Sierra?
Repair costs vary depending on the cause, ranging from $100 for simple wiring repairs to $500 or more for module replacement.
10. Can a software update fix the U0077 code on a 2017 GMC Sierra?
In some cases, a software update for the affected control module may resolve communication issues, but it depends on the specific problem diagnosed.
Discuss the causes and fixes for U0077 2017 GMC Sierra OBDII Code
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