AutoCodes – Generic – U18C0

U18C0 Code - Lost Communication With Suspension Control Module On High Speed CAN Bus

Quick Answer

Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Faulty Suspension Control Module, Suspension Control Module harness is open or shorted, Suspension 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: U18C0 indicates Lost Communication With Suspension Control Module On High Speed CAN Bus.
Common causes: Common causes include Faulty Suspension Control Module, Suspension Control Module harness is open or shorted, Suspension 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 475

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 09, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code U18C0 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 U18C0 - Lost Communication With Suspension Control Module On High Speed CAN Bus - AutoCodes.com — U18C0 Code - Lost Communication With Suspension Control Module On High Speed CAN Bus

What does this mean?

What are the Possible Causes of the DTC U18C0?

Faulty Suspension Control Module
Suspension Control Module harness is open or shorted
Suspension Control Module circuit poor electrical connection

How to Fix the DTC U18C0?

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 U18C0 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 U18C0 code?

Need more information on how to fix the U18C0 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U18C0 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

U18C0 Buick — Lost Communication With Suspension Control Module On High Speed CAN Bus
U18C0 Cadillac — Lost Communication With Suspension Control Module On High Speed CAN Bus
U18C0 Chevrolet — Lost Communication With Suspension Control Module On High Speed CAN Bus
U18C0 GMC — Lost Communication With Suspension Control Module On High Speed 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 U18C0 Code

1. What are some common symptoms of OBDII code U18C0?

Symptoms may include the suspension system malfunctioning, the suspension becoming stiff or bouncy, warning lights on the dashboard, and difficulty controlling the vehicle's ride quality.

2. What are the possible causes of OBDII code U18C0?

Causes can include faulty wiring or connections in the high-speed CAN bus network, a malfunctioning suspension control module, damaged control module components, or software issues.

3. How can I diagnose OBDII code U18C0?

Diagnosing this code typically involves using a professional OBDII scanner to retrieve the specific error code, checking the connection and wiring of the suspension control module, and inspecting the high-speed CAN bus network for any faults.

4. Can I still drive my vehicle with OBDII code U18C0 present?

It is not recommended to drive the vehicle with this code present, as it can affect the performance and safety of the suspension system. It's best to address the issue promptly.

5. How can I repair OBDII code U18C0?

Repairing this code may involve repairing or replacing damaged wiring or connections in the high-speed CAN bus network, replacing the suspension control module if necessary, or updating the control module software.

6. Is it possible to reset OBDII code U18C0 without fixing the underlying issue?

While you can clear the error code with an OBDII scanner, it is not recommended to do so without addressing the root cause. The issue will likely reoccur, and you may experience ongoing problems with the suspension system.

7. Can a DIY enthusiast fix OBDII code U18C0 at home?

Depending on your knowledge and experience with automotive repair, you may be able to address some aspects of this code at home, such as checking connections and wiring. However, complex issues may require professional diagnosis and repair.

8. How much does it cost to fix OBDII code U18C0 at a repair shop?

Repair costs can vary depending on the specific cause of the code and the labor rates of the repair shop. It's advisable to obtain quotes from different shops to compare prices.

9. Is OBDII code U18C0 a common issue in certain vehicle makes or models?

This particular code may be more common in vehicles equipped with a suspension control module and high-speed CAN bus network. It's always a good idea to check for any manufacturer recalls or service bulletins related to this issue.

10. Can extreme weather conditions contribute to triggering OBDII code U18C0?

Extreme weather conditions, such as extreme heat or cold, can potentially affect the electrical components involved in the high-speed CAN bus network, leading to communication issues and triggering the code.