AutoCodes – Buick – U18A6 Buick

U18A6 Buick 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 Buick 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 1,790

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 Buick 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 Buick - Lost Communication With Right Object Detection Control Module On Dedicated Bus 1 - AutoCodes.com — U18A6 Buick 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 Buick?

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 Buick?

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 Buick 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 Buick Code

What does the OBDII code U18A6 mean on a Buick?

The U18A6 code indicates a lost communication issue with the Right Object Detection Control Module on Dedicated Bus 1, typically part of the vehicle's blind spot monitoring system.

What are the common symptoms of the U18A6 code?

Symptoms include malfunctioning blind spot detection, illumination of the check engine or service warning lights, and possible loss of related safety features like rear cross-traffic alerts.

What causes the U18A6 code to appear?

Common causes include a faulty Right Object Detection Control Module, damaged wiring or connectors in the dedicated communication bus, or a software/firmware issue.

Can a weak battery trigger the U18A6 code?

Yes, low voltage or a weak battery can disrupt communication between modules and potentially trigger the U18A6 code.

How do you diagnose the U18A6 code?

Diagnosis typically involves scanning the vehicle with an OBDII scanner, inspecting the wiring and connectors to the Right Object Detection Control Module, and testing the module's functionality.

Is the U18A6 code safe to ignore?

Ignoring the U18A6 code can disable safety features like blind spot monitoring and rear cross-traffic alerts, which may increase the risk of collisions.

Can the U18A6 code clear itself?

The code may clear temporarily if the issue is intermittent, but it will likely return if the underlying problem is not resolved.

How much does it cost to fix the U18A6 code?

Repair costs vary depending on the issue, ranging from $100 for wiring repairs to $500 or more if the Right Object Detection Control Module needs replacement.

Can software updates resolve the U18A6 code?

In some cases, a software update from the manufacturer may fix communication issues between the modules.

What tools are needed to fix the U18A6 code?

Youâ€™ll need an OBDII scanner, a multimeter for testing electrical connections, and possibly manufacturer-specific diagnostic tools for module reprogramming or replacement.