AutoCodes – GMC – U18D0 GMC

U18D0 GMC Code - Lost Communication With Active Safety Control Module 2 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 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: U18D0 GMC indicates Lost Communication With Active Safety Control Module 2 On High Speed 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 634

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
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Code U18D0 GMC 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 U18D0 GMC - Lost Communication With Active Safety Control Module 2 On High Speed CAN Bus - AutoCodes.com — U18D0 GMC Code - Lost Communication With Active Safety Control Module 2 On High Speed CAN Bus

What does this mean?

What are the Possible Causes of the DTC U18D0 GMC?

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 U18D0 GMC?

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 U18D0 GMC 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 U18D0 GMC code?

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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 U18D0 GMC Code

1. What are the common symptoms of OBDII code U18D0 GMC?

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

2. What can cause the U18D0 GMC code to appear?

- The code U18D0 typically appears due to a communication failure between the vehicle's ECM and the Active Safety Control Module 2 on the high-speed CAN bus.

3. How can I diagnose the U18D0 GMC code?

- Diagnosing the U18D0 code may involve using an OBDII scanner to retrieve the code, checking for any other related trouble codes, and inspecting the wiring and connections between the ECM and Active Safety Control Module 2.

4. What are some repair tips for resolving the U18D0 GMC code?

- Repair tips may include checking and repairing any damaged wiring or connectors, ensuring proper connections between modules, clearing the code with a scanner, and performing a relearn procedure if necessary.

5. Can I drive my vehicle with the U18D0 GMC code present?

- It is not recommended to drive your vehicle with the U18D0 code present, as it may affect the proper functioning of safety features like traction control and stability control.

6. How serious is the U18D0 GMC code?

- The U18D0 code should be addressed promptly as it indicates a communication issue with an important safety module in the vehicle, potentially affecting the overall safety and performance of the vehicle.

7. Can I reset the U18D0 GMC code on my own?

- You can attempt to clear the U18D0 code on your own using an OBDII scanner, but it is important to diagnose and address the underlying issue causing the code to prevent it from reoccurring.

8. Do I need special tools to repair the U18D0 GMC code?

- While basic tools like an OBDII scanner and common hand tools may be sufficient for diagnosing and clearing the U18D0 code, specialized tools may be needed for more in-depth troubleshooting and repairs.

9. How much does it cost to fix the U18D0 GMC code?

- The cost of fixing the U18D0 code can vary depending on the underlying issue causing the code, the extent of repairs needed, and whether any parts need to be replaced. It is recommended to consult a professional for an accurate estimate.

10. Can a DIY enthusiast fix the U18D0 GMC code?

- Depending on their skill level and access to tools, a DIY enthusiast may be able to diagnose and potentially repair the U18D0 code. However, it is important to have a good understanding of automotive systems and safety protocols before attempting any repairs.