AutoCodes – Cadillac – U18C4 Cadillac

U18C4 Cadillac Code - Lost Communication With Video Processing Control Module On Low 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 Video Processing Control Module, Video Processing Control Module harness is open or shorted, Video Processing 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: U18C4 Cadillac indicates Lost Communication With Video Processing Control Module On Low Speed CAN Bus.
Common causes: Common causes include Faulty Video Processing Control Module, Video Processing Control Module harness is open or shorted, Video Processing 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.

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Code Popularity 427

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 U18C4 Cadillac 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 U18C4 Cadillac - Lost Communication With Video Processing Control Module On Low Speed CAN Bus - AutoCodes.com — U18C4 Cadillac Code - Lost Communication With Video Processing Control Module On Low Speed CAN Bus

What does this mean?

What are the Possible Causes of the DTC U18C4 Cadillac?

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

How to Fix the DTC U18C4 Cadillac?

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 U18C4 Cadillac 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 U18C4 Cadillac 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 U18C4 Cadillac Code

1. What are the common symptoms of OBDII code U18C4 in a Cadillac related to lost communication with the Video Processing Control Module on the Low Speed CAN Bus?

- Common symptoms may include issues with the vehicle's video display, navigation system, rearview camera, or other multimedia components.

2. What are the possible causes of OBDII code U18C4 in a Cadillac?

- The code U18C4 may be triggered by a faulty Video Processing Control Module, damaged wiring or connectors, a communication bus fault, or software glitches.

3. How can I diagnose the cause of OBDII code U18C4 in my Cadillac?

- Diagnosis typically involves checking the connections and wiring related to the Video Processing Control Module, performing a CAN bus communication test, and using a diagnostic scan tool to retrieve specific fault codes.

4. Are there any DIY repair tips for resolving OBDII code U18C4 in a Cadillac?

- DIY repair tips may include checking and repairing any damaged wiring or connectors, resetting the module, or updating the software if applicable. However, complex issues may require professional diagnosis and repair.

5. Can driving with OBDII code U18C4 in a Cadillac cause further damage to the vehicle?

- Driving with the U18C4 code may not cause immediate harm to the vehicle, but it can lead to issues with multimedia functionalities and potentially affect overall vehicle performance.

6. How much does it typically cost to repair OBDII code U18C4 in a Cadillac?

- The cost of repair can vary depending on the specific cause of the code and whether it requires replacement of components, wiring repairs, or software updates. It is recommended to consult a professional for an accurate estimate.

7. Is it safe to continue driving my Cadillac with OBDII code U18C4 present?

- While the vehicle may still be operational with the U18C4 code, it is advisable to address the issue promptly to prevent any further complications or potential safety concerns related to multimedia system malfunctions.

8. Can a software update fix OBDII code U18C4 in a Cadillac?

- In some cases, a software update provided by the manufacturer may resolve communication issues causing the U18C4 code. It is recommended to consult with a dealership or qualified technician for assistance.

9. How long does it take to repair OBDII code U18C4 in a Cadillac?

- The repair time for the U18C4 code can vary depending on the underlying cause and complexity of the issue. Simple fixes like reconnecting a loose wire may take a short time, while more intricate problems could require additional diagnosis and labor.

10. Will clearing the OBDII code U18C4 make it go away permanently?

- Clearing the code may temporarily remove the warning light, but if the underlying issue causing the U18C4 code is not addressed, it is likely to reappear. It is essential to diagnose and fix the root cause to prevent the code from returning.