AutoCodes – Lincoln – U0018 Lincoln

U0018 Lincoln Code - Medium Speed CAN Communication Bus (-) Shorted To Bus (+)

Quick Answer

Multiplexing is a method of sending 2 or more signals simultaneously over a single circuit. Common causes include Diagnosis of this Diagnostic Trouble Code (DTC) is accomplished via the vehicle symptom(s), Check for more codes, Faulty Control Module. 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: U0018 Lincoln indicates Medium Speed CAN Communication Bus (-) Shorted To Bus (+).
Common causes: Common causes include Diagnosis of this Diagnostic Trouble Code (DTC) is accomplished via the vehicle symptom(s), Check for more codes, Faulty Control Module.
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 Mar 29, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U0018 Lincoln Description

Multiplexing is a method of sending 2 or more signals simultaneously over a single circuit. Multiplexing allows 2 or more electronic modules (nodes) to communicate over a twisted wire pair [data (+) and data (-)] network. The information or messages that can be communicated on these wires consists of commands, status or data. Multiplexing reduces the weight of the vehicle by reducing the number of redundant components and electrical wiring. The vehicle has 4 module communication networks connected to the DLC, located under the instrument panel. The communication networks are: HEV High Speed Controller Area Network (HS-CAN), High Speed Controller Area Network (HS-CAN), Medium Speed Controller Area Network (MS-CAN) and Infotainment Controller Area Network (I-CAN). The Diagnostic Trouble Code (DTC) U0018 sets when a Medium Speed Controller Area Network (MS-CAN) fault was present at a point in time. The fault is not currently present since the module is communicating with the scan tool.

OBDII Code U0018 Lincoln - Medium Speed CAN Communication Bus (-) Shorted To Bus (+) - AutoCodes.com — U0018 Lincoln Code - Medium Speed CAN Communication Bus (-) Shorted To Bus (+)

What does this mean?

What are the Possible Causes of the DTC U0018 Lincoln?

Diagnosis of this Diagnostic Trouble Code (DTC) is accomplished via the vehicle symptom(s)
Check for more codes
Faulty Control Module
Control Module harness is open or shorted
Control Module circuit poor electrical connection

How to Fix the DTC U0018 Lincoln?

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 U0018 Lincoln 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 U0018 Lincoln code?

Need more information on how to fix the U0018 Lincoln code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U0018 Lincoln code diagnosed by a professional: Find a repair shop in your area

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 U0018 Lincoln Code

1. What are the common symptoms of OBDII code U0018 in a Lincoln vehicle?

- Common symptoms include intermittent or total loss of communication with various vehicle modules, issues with powertrain control module (PCM) operation, and malfunction indicator lamp (MIL) illumination.

2. What are the possible causes of OBDII code U0018 in a Lincoln vehicle?

- The code U0018 typically indicates a short between the Medium Speed Controller Area Network (CAN) bus positive and negative circuits. Common causes include damaged wiring, faulty CAN bus modules, or a short within the CAN bus circuit.

3. How can I diagnose OBDII code U0018 in my Lincoln vehicle?

- Diagnosis involves inspecting the wiring harness for damage, checking the CAN bus modules for proper operation, and using a diagnostic scan tool to retrieve specific trouble codes and data related to the U0018 code.

4. Can I drive my Lincoln vehicle with OBDII code U0018 present?

- It is not recommended to drive the vehicle with the U0018 code present, as it may lead to erratic behavior, potential drivability issues, and safety concerns due to communication malfunctions between critical vehicle systems.

5. How can I repair OBDII code U0018 in my Lincoln vehicle?

- Repairing the U0018 code involves identifying and repairing the short in the Medium Speed CAN bus circuit. This may require repairing damaged wiring, replacing faulty CAN bus modules, or addressing issues within the CAN bus communication system.

6. Is it possible to clear the OBDII code U0018 without fixing the underlying issue?

- Clearing the code without addressing the underlying issue will not resolve the problem. The root cause of the U0018 code must be identified and repaired to prevent the code from reoccurring and ensure proper vehicle operation.

7. Are there any common DIY fixes for OBDII code U0018 in a Lincoln vehicle?

- While some basic inspections like checking for visible wiring damage can be done by DIY enthusiasts, diagnosing and repairing the U0018 code often requires advanced diagnostic tools and expertise. It is advisable to consult a professional technician for accurate diagnosis and repair.

8. Can extreme weather conditions impact the occurrence of OBDII code U0018 in a Lincoln vehicle?

- Extreme weather conditions, such as excessive heat or moisture, can potentially exacerbate wiring issues and lead to shorts in the CAN bus circuit, increasing the likelihood of triggering the U0018 code. It is essential to keep the vehicle properly maintained to minimize the impact of weather-related issues.