AutoCodes – GMC – U18CF GMC

U18CF GMC Code - Lost Communication With Active Safety Control Module 1 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 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: U18CF GMC indicates Lost Communication With Active Safety Control Module 1 On High Speed 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 577

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 U18CF 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 U18CF GMC - Lost Communication With Active Safety Control Module 1 On High Speed CAN Bus - AutoCodes.com — U18CF GMC Code - Lost Communication With Active Safety Control Module 1 On High Speed CAN Bus

What does this mean?

What are the Possible Causes of the DTC U18CF GMC?

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 U18CF 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 U18CF 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.

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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 U18CF GMC Code

1. What are common symptoms of OBDII code U18CF GMC (Lost Communication With Active Safety Control Module 1 On High Speed CAN Bus)?

- Common symptoms include malfunction indicator light (MIL) illumination, loss of communication with active safety systems, and potential loss of certain vehicle safety features.

2. What are possible causes of the U18CF code in a GMC vehicle?

- Possible causes include a faulty Active Safety Control Module, issues with the High Speed CAN Bus communication network, wiring harness problems, or a software glitch.

3. How can I diagnose the U18CF code in my GMC vehicle?

- Diagnosing the U18CF code typically involves using a professional OBDII scanner to retrieve the fault codes and conducting a thorough inspection of the Active Safety Control Module, wiring, and CAN Bus network.

4. What are some repair tips for fixing the U18CF code in a GMC vehicle?

- Repair tips may include checking and repairing any damaged wiring or connectors, reprogramming the Active Safety Control Module, ensuring proper power and ground connections, or replacing the module if necessary.

5. Can I drive my GMC vehicle with the U18CF code present?

- It is not recommended to drive the vehicle with the U18CF code present, as it may result in the loss of essential safety features. It is best to address the issue promptly to ensure the vehicle's safety systems are functioning correctly.

6. How much does it typically cost to repair the U18CF code in a GMC vehicle?

- The cost of repairing the U18CF code can vary depending on the specific cause of the issue. Costs may include parts, labor, and diagnostic fees, so it is advisable to consult with a professional mechanic for an accurate estimate.

7. Can the U18CF code be a recurring issue in GMC vehicles?

- The U18CF code can be a recurring issue if the root cause is not properly addressed during the initial repair. It is crucial to diagnose the problem accurately and make necessary repairs to prevent the code from reappearing.

8. Are there any recalls or technical service bulletins related to the U18CF code in GMC vehicles?

- It is advisable to check with GMC dealerships or online resources for any recalls or technical service bulletins related to the U18CF code to see if there are any known issues or remedies provided by the manufacturer.

9. How long does it typically take to repair the U18CF code in a GMC vehicle?

- The repair time for the U18CF code can vary depending on the complexity of the issue and the availability of parts. Simple fixes may take a few hours, while more involved repairs could take longer.

10. Is it possible to prevent the U18CF code from occurring in my GMC vehicle?

- While some causes of the U18CF code may be unavoidable, regular maintenance, careful handling of the vehicle's electronics, and prompt attention to any warning lights or abnormal behaviors can help prevent this code from occurring.