AutoCodes – Generic – U18B6

U18B6 Code - Lost Communication With Active Safety Control Module 1 On Chassis Expansion CAN Bus

Quick Answer

Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Faulty Active Safety Control Module 1, Active Safety Control Module 1 harness is open or shorted, Active Safety Control Module 1 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: U18B6 indicates Lost Communication With Active Safety Control Module 1 On Chassis Expansion CAN Bus.
Common causes: Common causes include Faulty Active Safety Control Module 1, Active Safety Control Module 1 harness is open or shorted, Active Safety Control Module 1 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 554

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 U18B6 Description

Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the devices. The devices have prerecorded information about what messages are needed to be exchanged on the serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used by the receiver device as an availability indication of the transmitter device. Each message contains the identification number of the transmitter device. The Diagnostic Trouble Code (DTC) will set a supervised periodic message that includes the transmitter device availability that has not been received.

OBDII Code U18B6 - Lost Communication With Active Safety Control Module 1 On Chassis Expansion CAN Bus - AutoCodes.com — U18B6 Code - Lost Communication With Active Safety Control Module 1 On Chassis Expansion CAN Bus

What does this mean?

What are the Possible Causes of the DTC U18B6?

Faulty Active Safety Control Module 1
Active Safety Control Module 1 harness is open or shorted
Active Safety Control Module 1 circuit poor electrical connection

How to Fix the DTC U18B6?

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 U18B6 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 U18B6 code?

Need more information on how to fix the U18B6 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U18B6 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

U18B6 Buick — Lost Communication With Active Safety Control Module 1 On Chassis Expansion CAN Bus
U18B6 Cadillac — Lost Communication With Active Safety Control Module 1 On Chassis Expansion CAN Bus
U18B6 Chevrolet — Lost Communication With Active Safety Control Module 1 On Chassis Expansion CAN Bus
U18B6 GMC — Lost Communication With Active Safety Control Module 1 On Chassis Expansion CAN 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 U18B6 Code

1. What are the common symptoms of OBDII code U18B6?

- Common symptoms include loss of communication with the active safety control module, warning lights on the dashboard, and potential loss of certain safety features.

2. What are the possible causes of OBDII code U18B6?

- Possible causes include a faulty active safety control module, damaged wiring or connectors in the CAN bus system, or a software issue within the control module.

3. How can I diagnose the issue related to OBDII code U18B6?

- Diagnosis involves using a professional OBDII scanner to retrieve the code, checking for other related trouble codes, and inspecting the wiring and connectors for any visible damage.

4. Is it safe to drive with OBDII code U18B6 present?

- It is not recommended to drive with this code present, as it may indicate a potential issue with important safety systems in the vehicle.

5. How can I repair OBDII code U18B6?

- Repair options include repairing or replacing any damaged wiring or connectors, reprogramming the active safety control module, or replacing the module if it is deemed faulty.

6. Can OBDII code U18B6 be a false alarm?

- While rare, it is possible for this code to be triggered by a temporary communication glitch. Clearing the code and monitoring the situation may help determine if it was a false alarm.

7. Will OBDII code U18B6 cause the vehicle to fail an emissions test?

- The presence of this code alone may not cause the vehicle to fail an emissions test, but it should still be addressed to ensure proper functioning of safety systems.

8. How much does it typically cost to repair OBDII code U18B6?

- Repair costs can vary depending on the exact cause of the issue, but they may range from a few hundred to a few thousand dollars, including parts and labor.

9. Can I reset OBDII code U18B6 on my own?

- You can reset the code using an OBDII scanner, but it is important to address the underlying issue causing the code to prevent it from reoccurring.

10. How long does it take to repair OBDII code U18B6?

- The repair time can vary based on the specific repair needed, but it may take anywhere from a few hours to a full day to diagnose and fix the issue.