AutoCodes – GMC – U18A6 GMC

U18A6 GMC Code - Lost Communication With Right Object Detection Control Module On Dedicated Bus 1

Quick Answer

The side object sensor modules use radar to determine the presence of objects nearby. Common causes include Faulty Right Object Detection Control Module, Right Object Detection Control Module harness is open or shorted, Right Object Detection 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: U18A6 GMC indicates Lost Communication With Right Object Detection Control Module On Dedicated Bus 1.
Common causes: Common causes include Faulty Right Object Detection Control Module, Right Object Detection Control Module harness is open or shorted, Right Object Detection 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 2,984

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 Jun 08, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U18A6 GMC Description

The side object sensor modules use radar to determine the presence of objects nearby. The left side object sensor is the master that communicates on serial data. There is a private communication network between the left and right sensors. The scan tool can communicate only with the left sensor. Side blind zone alert is active when the vehicle is out of the park or the parking brake is off on manual transmission vehicles. If a vehicle is detected in the side blind zone, the warning symbols will illuminate on the appropriate side. The warning symbols will vary brightness based on the ambient light conditions. When an object is detected in the left side blind zone, the side object sensor module sends a message to the right sensor through serial data. The right sensor then supplies voltage to illuminate the visual indicator on the left side outside rearview mirror. When an object is detected in the right-side blind zone, the right side object sensor will supply a voltage to illuminate the visual indicator on the right side outside rearview mirror. The Diagnostic Trouble Code (DTC) will set a supervised periodic message that includes the transmitter device availability that has not been received.

OBDII Code U18A6 GMC - Lost Communication With Right Object Detection Control Module On Dedicated Bus 1 - AutoCodes.com — U18A6 GMC Code - Lost Communication With Right Object Detection Control Module On Dedicated Bus 1

What does this mean?

What are the Possible Causes of the DTC U18A6 GMC?

Faulty Right Object Detection Control Module
Right Object Detection Control Module harness is open or shorted
Right Object Detection Control Module circuit poor electrical connection

How to Fix the DTC U18A6 GMC?

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 U18A6 GMC 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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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 U18A6 GMC Code

1. What are common symptoms of OBDII code U18A6 GMC?

- Common symptoms include malfunctioning right object detection system, warning lights on the dashboard, and loss of communication with the module.

2. What can cause the OBDII code U18A6 GMC to occur?

- The code can be triggered by issues such as a faulty right object detection control module, damaged wiring or connectors, or communication bus faults.

3. How can I diagnose the cause of the U18A6 code?

- Diagnosis involves checking the right object detection control module, inspecting wiring and connectors for damage, and testing the communication bus for faults using a diagnostic scanner.

4. Can a blown fuse cause the U18A6 code to appear?

- Yes, a blown fuse related to the right object detection system can lead to a loss of communication with the module and trigger the U18A6 code.

5. What is the recommended repair for the U18A6 code?

- The recommended repair involves addressing the root cause of the communication loss, which may include replacing the right object detection control module, repairing damaged wiring, or fixing communication bus issues.

6. Will resetting the code make it go away permanently?

- Simply resetting the code without addressing the underlying issue will not make it go away permanently. The problem needs to be diagnosed and fixed to prevent the code from reappearing.

7. Can extreme weather conditions trigger the U18A6 code?

- Yes, extreme weather conditions like moisture or temperature fluctuations can affect the right object detection system components and lead to communication errors triggering the U18A6 code.

8. Is it safe to continue driving with the U18A6 code present?

- It is not recommended to continue driving with the U18A6 code as it indicates a potential issue with a crucial safety system like the object detection module.

9. How long does it typically take to repair the U18A6 code?

- The repair time for the U18A6 code can vary depending on the exact cause of the issue, but it may take anywhere from a few hours to a day for diagnosis and repair.

10. Can a DIY enthusiast fix the U18A6 code at home?

- Depending on their skill level and access to tools, a DIY enthusiast may be able to address simple causes of the U18A6 code like checking and repairing wiring connections, but more complex issues may require professional help.