AutoCodes – Chevrolet – U0020 2018 Chevrolet Silverado

U0020 2018 Chevrolet Silverado Code - Low Speed CAN Bus

Quick Answer

Devices connected to the General Motors Local Area Network (GMLAN) serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include If other codes are present, diagnose other codes first, 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: U0020 2018 Chevrolet Silverado indicates Low Speed CAN Bus.
Common causes: Common causes include If other codes are present, diagnose other codes first, 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 284

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
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code U0020 2018 Chevrolet Silverado Description

Devices connected to the General Motors 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. The devices have programmed information about what messages need to be exchanged on the serial data circuits. The messages are also supervised, and some periodic messages are used by the receiver device as an availability indication of the transmitter device. The Diagnostic Trouble Code (DTC) will be set when a supervised periodic message that includes the transmitter device availability has not been received.

OBDII Code U0020 2018 Chevrolet Silverado - Low Speed CAN Bus - AutoCodes.com — U0020 2018 Chevrolet Silverado Code - Low Speed CAN Bus

What does this mean?

What are the Possible Causes of the DTC U0020 2018 Chevrolet Silverado?

If other codes are present, diagnose other codes first
Faulty Control Module
Control Module harness is open or shorted
Control Module circuit poor electrical connection

How to Fix the DTC U0020 2018 Chevrolet Silverado?

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 does this mean?

Code Tech Notes

Controller Area Network (CAN)

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the U0020 2018 Chevrolet Silverado 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 U0020 2018 Chevrolet Silverado code?

Need more information on how to fix the U0020 2018 Chevrolet Silverado 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 U0020 2018 Chevrolet Silverado Code

What does OBDII code U0020 mean for a 2018 Chevrolet Silverado?

U0020 indicates a problem with the Low Speed CAN Bus communication between modules in the vehicle, suggesting there may be a failure in the communication network.

What are common symptoms of the U0020 code in a Chevrolet Silverado?

Common symptoms include warning lights on the dashboard, erratic behavior of electronic components, and potential issues with features like traction control or stability control.

What could cause the U0020 code to trigger in a 2018 Chevrolet Silverado?

Causes may include damaged wiring or connectors in the CAN Bus system, faulty modules, or interference from other electrical components.

How can I diagnose the U0020 code in my Silverado?

Start by using an OBD-II scanner to confirm the code. Then, visually inspect the wiring and connectors for damage, and check for any other related codes that may provide additional context.

What repairs might be necessary for the U0020 code?

Repairs could involve repairing or replacing damaged wiring, fixing or replacing faulty modules, or ensuring solid connections in the CAN Bus system.

Can I drive my Chevrolet Silverado with the U0020 code?

While it may be possible to drive the vehicle, it is not recommended, as the underlying communication issue could affect critical vehicle systems and safety features.

What tools do I need to troubleshoot the U0020 code?

Basic tools include an OBD-II scanner for reading codes, a multimeter for testing electrical connections, and basic hand tools for inspecting and repairing wiring.

Is it safe to clear the U0020 code without fixing the issue?

Clearing the code without addressing the root cause is not advisable, as the issue may reoccur and could affect vehicle performance or safety.

How much might it cost to repair the U0020 code in a Silverado?

Repair costs can vary widely based on the specific issue but may range from $100 to several hundred dollars for wiring repairs or module replacements.