AutoCodes – Generic – U18B7

U18B7 Code - Lost Communication With Active Safety Control Module 2 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 2, Active Safety Control Module 2 harness is open or shorted, Active Safety Control Module 2 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: U18B7 indicates Lost Communication With Active Safety Control Module 2 On Chassis Expansion CAN Bus.
Common causes: Common causes include Faulty Active Safety Control Module 2, Active Safety Control Module 2 harness is open or shorted, Active Safety Control Module 2 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 557

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 U18B7 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 U18B7 - Lost Communication With Active Safety Control Module 2 On Chassis Expansion CAN Bus - AutoCodes.com — U18B7 Code - Lost Communication With Active Safety Control Module 2 On Chassis Expansion CAN Bus

What does this mean?

What are the Possible Causes of the DTC U18B7?

Faulty Active Safety Control Module 2
Active Safety Control Module 2 harness is open or shorted
Active Safety Control Module 2 circuit poor electrical connection

How to Fix the DTC U18B7?

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 U18B7 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 U18B7 code?

Need more information on how to fix the U18B7 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U18B7 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

U18B7 Buick — Lost Communication With Active Safety Control Module 2 On Chassis Expansion CAN Bus
U18B7 Cadillac — Lost Communication With Active Safety Control Module 2 On Chassis Expansion CAN Bus
U18B7 Chevrolet — Lost Communication With Active Safety Control Module 2 On Chassis Expansion CAN Bus
U18B7 GMC — Lost Communication With Active Safety Control Module 2 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 U18B7 Code

1. What are common symptoms of OBDII code U18B7?

- Common symptoms include loss of communication with Active Safety Control Module 2, warning lights on the dashboard, and potential issues with active safety features.

2. What could cause OBDII code U18B7 to trigger?

- This code is usually triggered by a communication error between the vehicle's main computer and the Active Safety Control Module 2 on the Chassis Expansion CAN Bus.

3. How can I diagnose the issue related to code U18B7?

- Diagnosing the issue involves checking the wiring and connections related to the Active Safety Control Module 2, as well as scanning the system for any other related trouble codes.

4. What are some possible repair tips for resolving code U18B7?

- Repair tips may include checking and repairing any damaged wiring, ensuring proper connections, resetting the system, and reprogramming the Active Safety Control Module 2 if necessary.

5. Can code U18B7 be safely ignored?

- Ignoring this code is not recommended, as it may lead to safety system malfunctions and compromise the vehicle's active safety features.

6. Is it safe to drive with OBDII code U18B7 present?

- It is not advisable to drive with this code present, as it indicates a potential issue with the vehicle's active safety systems that could affect overall safety.

7. How much does it typically cost to repair OBDII code U18B7?

- The cost of repairing this code can vary depending on the underlying cause, but it may involve labor costs for diagnosis and repair, as well as potential part replacement expenses.

8. Can a DIY enthusiast fix OBDII code U18B7 at home?

- While some simple checks like inspecting connections can be done at home, resolving code U18B7 may require specialized tools and expertise, so it's often best left to professional mechanics.

9. Will resetting the OBDII system clear code U18B7?

- Resetting the OBDII system may temporarily clear the code, but if the underlying issue is not addressed, the code is likely to reappear after driving the vehicle for some time.

10. How urgent is it to address OBDII code U18B7?

- It is recommended to address code U18B7 promptly to ensure the proper functioning of the vehicle's active safety systems and maintain overall safety while driving.