AutoCodes – Generic – U18AF

U18AF Code - Lost Communications With Telematics Communications Interface Control Module On Ethernet Bus

Quick Answer

At the core of the infotainment system is the Radio Ethernet Audio Video Bridging switch which communicates directly to each contributing Infotainment control module terminator. Common causes include Faulty Telematics Communications Interface Control Module, Telematics Communications Interface Control Module harness is open or shorted, Telematics Communications Interface 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: U18AF indicates Lost Communications With Telematics Communications Interface Control Module On Ethernet Bus.
Common causes: Common causes include Faulty Telematics Communications Interface Control Module, Telematics Communications Interface Control Module harness is open or shorted, Telematics Communications Interface 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 1,731

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 U18AF Description

At the core of the infotainment system is the Radio Ethernet Audio Video Bridging switch which communicates directly to each contributing Infotainment control module terminator. The Ethernet harness consists of twisted pair wires from point to point. Each control module on the Ethernet infotainment system sends/receives data at 100 Mbit/s to/from a specified port at the Radio. The Radio Ethernet will also be used to program USB software update files to the control modules connected to the Ethernet ports. The Diagnostic Trouble Code (DTC) will set a supervised periodic message that includes the transmitter device availability that has not been received.

OBDII Code U18AF - Lost Communications With Telematics Communications Interface Control Module On Ethernet Bus - AutoCodes.com — U18AF Code - Lost Communications With Telematics Communications Interface Control Module On Ethernet Bus

What does this mean?

What are the Possible Causes of the DTC U18AF?

Faulty Telematics Communications Interface Control Module
Telematics Communications Interface Control Module harness is open or shorted
Telematics Communications Interface Control Module circuit poor electrical connection

How to Fix the DTC U18AF?

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 U18AF 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 U18AF code?

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Need Help with the Code?

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Information for Specific Makes

U18AF Buick — Lost Communications With Telematics Communications Interface Control Module On Ethernet Bus
U18AF Cadillac — Lost Communications With Telematics Communications Interface Control Module On Ethernet Bus
U18AF Chevrolet — Lost Communications With Telematics Communications Interface Control Module On Ethernet Bus
U18AF GMC — Lost Communications With Telematics Communications Interface Control Module On Ethernet 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 U18AF Code

1. What are common symptoms of OBDII code U18AF?

- Common symptoms include loss of communication with the telematics control module, malfunctioning vehicle telematics system, and potential warning lights on the dashboard.

2. What are possible causes of OBDII code U18AF?

- Possible causes include faulty telematics communications interface control module, damaged wiring or connectors in the ethernet bus, software issues, or a malfunctioning ECM.

3. How can I diagnose OBDII code U18AF?

- Diagnose the code by checking the wiring and connectors for damage, testing the telematics control module, and verifying the communication signals on the ethernet bus using a diagnostic scanner.

4. Can I still drive my vehicle with OBDII code U18AF?

- It is not recommended to drive the vehicle with this code present, as it may affect the functionality of the telematics system and potentially lead to other issues.

5. How do I repair OBDII code U18AF?

- Repair options include replacing the faulty telematics communications interface control module, repairing damaged wiring or connectors, updating software, or reprogramming the ECM.

6. Is OBDII code U18AF a common issue in certain vehicle models?

- This code may be more common in vehicles equipped with advanced telematics systems that rely on an ethernet bus for communication.

7. Can a DIY enthusiast fix OBDII code U18AF at home?

- Depending on the underlying cause, DIY enthusiasts with advanced automotive repair skills and access to diagnostic tools may be able to address this code at home.

8. Will resetting the fault codes make OBDII code U18AF go away?

- Resetting the fault codes may temporarily clear the code, but it will likely return if the underlying issue with the telematics communications interface control module or ethernet bus is not addressed.

9. How long does it typically take to repair OBDII code U18AF?

- The repair time can vary depending on the exact cause of the issue, but it may take a few hours to a full day to diagnose and fix the problem.

10. Is OBDII code U18AF a serious issue that requires immediate attention?

- It is recommended to address this code promptly to prevent potential issues with the telematics system and ensure the vehicle's overall functionality and safety.