AutoCodes – GMC – U2099 2018 GMC Sierra

U2099 2018 GMC Sierra Code - High Speed Communication Enable Circuit

Quick Answer

The Body Control Module (BCM) activates the ignition circuit, when the ignition key is in ACC, ON or START. Common causes include Faulty Body Control Module (BCM), Body Control Module harness is open or shorted, Body Control Module 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: U2099 2018 GMC Sierra indicates High Speed Communication Enable Circuit.
Common causes: Common causes include Faulty Body Control Module (BCM), Body Control Module harness is open or shorted, Body Control Module 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 253

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 24, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U2099 2018 GMC Sierra Description

The Body Control Module (BCM) activates the ignition circuit, when the ignition key is in ACC, ON or START. The ignition circuit wakes up the devices for serial data bus communication. The Diagnostic Trouble Code (DTC) will set when the BCM senses a short to ground on the ignition circuit.

OBDII Code U2099 2018 GMC Sierra - High Speed Communication Enable Circuit - AutoCodes.com — U2099 2018 GMC Sierra Code - High Speed Communication Enable Circuit

What does this mean?

What are the Possible Causes of the DTC U2099 2018 GMC Sierra?

Faulty Body Control Module (BCM)
Body Control Module harness is open or shorted
Body Control Module circuit poor electrical connection

How to Fix the DTC U2099 2018 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 U2099 2018 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 U2099 2018 GMC Sierra code?

Need more information on how to fix the U2099 2018 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U2099 2018 GMC Sierra 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 U2099 2018 GMC Sierra Code

1. What does the OBDII code U2099 for a 2018 GMC Sierra indicate?

The code U2099 specifically relates to the High-Speed Communication Enable Circuit in the GMC Sierra's onboard diagnostics system.

2. What are the common symptoms of OBDII code U2099 in a 2018 GMC Sierra?

Common symptoms include issues with the vehicle's communication systems, such as the inability to connect to diagnostic tools or certain sensors malfunctioning.

3. What are the potential causes of OBDII code U2099 in a 2018 GMC Sierra?

Potential causes may include damaged wiring or connectors related to the high-speed communication circuit, faults in the control modules, or software glitches.

4. How can I diagnose the OBDII code U2099 in my 2018 GMC Sierra?

Diagnosing this code typically involves inspecting the wiring and connectors associated with the high-speed communication circuit, checking for loose connections, and using diagnostic tools to identify specific faults.

5. Can I still drive my 2018 GMC Sierra with the U2099 code present?

In most cases, it is safe to drive the vehicle with the U2099 code present, especially if there are no noticeable performance issues. However, it is recommended to have the issue diagnosed and repaired as soon as possible.

6. How can I repair the OBDII code U2099 in my 2018 GMC Sierra?

Repairing the U2099 code may involve fixing any damaged wiring or connectors, replacing faulty control modules, and clearing the code with a diagnostic tool after the repairs are completed.

7. Is the OBDII code U2099 in a 2018 GMC Sierra a serious issue?

While the U2099 code itself may not directly impact the vehicle's drivability, it is essential to address the underlying communication circuit problem to prevent potential complications with other vehicle systems.

8. Can a DIY enthusiast fix the OBDII code U2099 in a 2018 GMC Sierra?

Depending on their skill level and access to tools, a knowledgeable DIY enthusiast may be able to diagnose and repair the U2099 code. However, it is recommended to seek professional help if unsure.

9. Will resetting the OBDII code U2099 in my 2018 GMC Sierra make it go away permanently?

Resetting the code may temporarily clear the warning light, but if the underlying issue causing the U2099 code is not addressed, it is likely to reappear. It is crucial to fix the root cause for a permanent solution.

10. How much can I expect to pay for repairing the OBDII code U2099 in a 2018 GMC Sierra?

The cost of repairing the U2099 code can vary based on the extent of the issue, parts needed, and labor costs. It is advisable to consult a mechanic for an accurate estimate based on your specific situation.