Engine-Codes.com
Engine-Codes – GMC – U1128 GMC

U1128 GMC Code - Lost Communications With Radio

Quick Answer

The U1128 GMC code indicates that there is a communication error between the vehicle's onboard computer system and the radio. Common causes include Loose or corroded wiring connections between the radio and the vehicle's computer system, Faulty radio unit or antenna, Software glitches in the vehicle's computer system. 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
U1128 GMC indicates Lost Communications With Radio.
Common causes
Common causes include Loose or corroded wiring connections between the radio and the vehicle's computer system, Faulty radio unit or antenna, Software glitches in the vehicle's computer system.
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 13, 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 U1128 GMC Description

The U1128 GMC code indicates that there is a communication error between the vehicle's onboard computer system and the radio. This can result in the loss of important data exchange between these two components, leading to various issues with the radio's functionality and potentially affecting other systems in the vehicle. When the communication is lost, it can prevent the radio from receiving or sending signals properly, resulting in a lack of audio output, display malfunctions, or even complete radio failure.

OBDII Code U1128 GMC - Lost Communications With Radio
U1128 GMC Code - Lost Communications With Radio

Common Causes of U1128 GMC

  1. Loose or corroded wiring connections between the radio and the vehicle's computer system
  2. Faulty radio unit or antenna
  3. Software glitches in the vehicle's computer system
  4. Electrical interference from aftermarket electronic devices
  5. Water damage to the radio unit or wiring connections

Symptoms of U1128 GMC

  1. Loss of radio functionality (no sound, display issues)
  2. Inability to change radio stations or adjust volume
  3. Radio turning on and off intermittently
  4. Error message displayed on the radio screen
  5. Illumination of the check engine light

How to Fix U1128 GMC

  1. Begin by checking the wiring connections between the radio and the vehicle's computer system for any signs of damage or corrosion. Repair or replace any faulty connections.
  2. Test the radio unit and antenna for proper functionality. Replace any components that are malfunctioning.
  3. Clear the diagnostic trouble codes from the vehicle's computer system using a diagnostic scanner.
  4. Reset the radio unit by disconnecting the battery for a few minutes and then reconnecting it.
  5. Perform a test drive to ensure that the communication between the radio and the vehicle's computer system has been restored.

Cost to Fix U1128 GMC

The typical repair costs for addressing the U1128 GMC code can vary depending on the specific cause of the communication error. In general, the cost of parts such as wiring connections, radio units, or antennas can range from $100 to $500. Labor costs at auto repair shops typically range from $80 to $150 per hour. The total repair cost may therefore fall within the range of $200 to $800, including parts and labor. It is advisable to consult with a qualified technician for a more accurate estimate based on the specific diagnosis and repair needed for your vehicle.

Need more information about the U1128 GMC code?

Need more information on how to fix the U1128 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U1128 GMC 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 U1128 GMC Code

1. What are the common symptoms of OBDII code U1128 GMC (Lost Communications With Radio)?

- Common symptoms include radio not working, loss of communication with other modules, and warning lights on the dashboard.

2. What are some possible causes of the U1128 GMC trouble code?

- Possible causes may include a faulty radio unit, damaged wiring or connectors, a bad fuse, or a malfunctioning communication module.

3. How can I diagnose the U1128 GMC code related to lost communications with the radio?

- You can start by checking the radio connections, fuses, and wiring harness for any visible damage. Using a diagnostic scanner to check for communication errors between modules is also recommended.

4. Can a dead battery cause the U1128 GMC trouble code to appear?

- Yes, a dead or low battery can sometimes trigger communication issues between modules, leading to the U1128 code being stored in the system.

5. Is it safe to continue driving with the U1128 GMC code present?

- While the vehicle may still be operable with this code, it is recommended to address the issue promptly as it may affect the overall functionality of the vehicle's electronic systems.

6. What are some repair tips for addressing the U1128 GMC code?

- Start by checking and repairing any damaged wiring or connectors related to the radio system. Resetting the code using a diagnostic scanner after making repairs can help clear the issue.

7. Can I reset the U1128 GMC trouble code myself?

- Yes, you can use an OBDII scanner to reset the code after addressing the underlying issue with the radio communication. However, if the problem persists, further diagnosis may be required.

8. Will disconnecting the battery reset the U1128 GMC trouble code?

- Disconnecting the battery may reset the code temporarily, but it is important to address the root cause of the communication issue to prevent the code from reappearing.

9. How much does it typically cost to repair the U1128 GMC trouble code?

- The cost of repair can vary depending on the underlying cause of the communication issue. Simple fixes like repairing wiring may be relatively inexpensive, while replacing the radio unit could be more costly.

10. Can a DIY enthusiast fix the U1128 GMC trouble code issue?

- Depending on the specific cause of the code, DIY enthusiasts with automotive repair knowledge may be able to address the U1128 GMC issue by checking connections, fuses, and wiring before seeking professional help if needed.

Discuss the causes and fixes for U1128 GMC OBDII Code

Submit a New Comment

Code U1128 GMC comments

No comments found for this page.