AutoCodes – Chevrolet – U0028 Chevrolet

U0028 Chevrolet Code - Media Oriented Systems Transport Bus

Quick Answer

The Media Oriented Systems Transport (MOST) bus consists of a physical ring in which multimedia devices share audio, video and infotainment system control data. Common causes include Faulty Audio Unit (Radio), Audio Unit harness is open or shorted, Audio Unit 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: U0028 Chevrolet indicates Media Oriented Systems Transport Bus.
Common causes: Common causes include Faulty Audio Unit (Radio), Audio Unit harness is open or shorted, Audio Unit 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 8,291

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 19, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U0028 Chevrolet Description

The Media Oriented Systems Transport (MOST) bus consists of a physical ring in which multimedia devices share audio, video and infotainment system control data. Each device on the MOST bus transmits and receives data via the MOST Bus Serial Data (+/- transmit/receive) circuits. The MOST bus diagnostic master is the Radio. The MOST control circuit is connected to each device on the MOST bus. Each device provides a 12 V signal on the MOST control circuit. The Radio initiates communication on the MOST bus at Ignition ON by toggling the MOST control circuit low for 100 ms. Once each device recognizes the wakeup signal from the Radio on the MOST control circuit, they will respond to the Radio on the MOST bus to indicate no faults are present and normal communications will commence. The Diagnostic Trouble Code (DTC) sets when a fault occurs on transmit, receive, electronic control lines, or internal device failure.

OBDII Code U0028 Chevrolet - Media Oriented Systems Transport Bus - AutoCodes.com — U0028 Chevrolet Code - Media Oriented Systems Transport Bus

What does this mean?

What are the Possible Causes of the DTC U0028 Chevrolet?

Faulty Audio Unit (Radio)
Audio Unit harness is open or shorted
Audio Unit circuit poor electrical connection

How to Fix the DTC U0028 Chevrolet?

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 U0028 Chevrolet 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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Need Help with the Code?

Get the U0028 Chevrolet code diagnosed by a professional: Find a repair shop in your area

Information for Specific Chevrolet Models

U0028 2014 Chevrolet Silverado — Media Oriented Systems Transport Bus
U0028 2015 Chevrolet Silverado — Media Oriented Systems Transport Bus
U0028 2016 Chevrolet Silverado — Media Oriented Systems Transport Bus
U0028 2017 Chevrolet Silverado — Media Oriented Systems Transport Bus
U0028 2018 Chevrolet Silverado — Media Oriented Systems Transport Bus

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 U0028 Chevrolet Code

1. What is OBDII code U0028 in a Chevrolet related to the Media Oriented Systems Transport Bus (MOST)?

Code U0028 indicates a communication error on the MOST bus network in the vehicle's multimedia system.

2. What are common symptoms of OBDII code U0028 in a Chevrolet?

Common symptoms include issues with the vehicle's infotainment system, such as loss of audio, navigation, or display functions.

3. What are possible causes of OBDII code U0028 in a Chevrolet?

Possible causes include a faulty MOST bus controller, damaged wiring or connectors in the MOST network, or a malfunction in a multimedia system component.

4. How can I diagnose OBDII code U0028 in a Chevrolet?

Diagnosis typically involves using a diagnostic scanner to pinpoint the specific location of the communication error on the MOST bus network and testing the related components for proper functionality.

5. Can I repair OBDII code U0028 in a Chevrolet myself?

If you have experience with automotive electronics and wiring, you may be able to repair this code yourself by inspecting and repairing any damaged wiring, connectors, or components in the MOST network.

6. Is it safe to drive with OBDII code U0028 in a Chevrolet?

It is generally safe to drive with this code, but you may experience limitations in the functionality of the multimedia system until the issue is resolved.

7. How much does it cost to fix OBDII code U0028 in a Chevrolet?

The cost of repair can vary depending on the specific cause of the code, but it may involve replacing a faulty MOST bus controller, repairing wiring or connectors, or addressing issues with multimedia system components.

8. Can resetting the OBDII system clear code U0028 in a Chevrolet?

Resetting the OBDII system may temporarily clear the code, but it is important to diagnose and address the underlying issue to prevent the code from reoccurring.

9. Are there any recalls or technical service bulletins related to OBDII code U0028 in Chevrolet vehicles?

It's recommended to check with Chevrolet dealerships or online resources for any recalls or technical service bulletins related to OBDII code U0028 to see if there are known issues or solutions.

10. How long does it take to repair OBDII code U0028 in a Chevrolet?

The repair time can vary depending on the complexity of the issue, but it may take a few hours to a full day to diagnose and fix the problem causing code U0028 in a Chevrolet.