AutoCodes – Mercury – U0009 Mercury

U0009 Mercury Code - High 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: U0009 Mercury indicates High 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 737

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 U0009 Mercury 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) U0009 sets when a High Speed Controller Area Network (HS-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 U0009 Mercury - High Speed CAN Communication Bus (-) Shorted To Bus (+) - AutoCodes.com — U0009 Mercury Code - High Speed CAN Communication Bus (-) Shorted To Bus (+)

What does this mean?

What are the Possible Causes of the DTC U0009 Mercury?

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 U0009 Mercury?

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 U0009 Mercury 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 U0009 Mercury code?

Need more information on how to fix the U0009 Mercury code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U0009 Mercury 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 U0009 Mercury Code

1. What are the common symptoms of OBDII code U0009 in a Mercury vehicle?

- Common symptoms include communication issues with various control modules, erratic behavior in the vehicle's electronic systems, and possible illumination of the check engine light.

2. What causes the U0009 code indicating "High Speed CAN Communication Bus (-) Shorted To Bus (+)" in a Mercury?

- The U0009 code is typically triggered by a short circuit between the high-speed CAN communication bus negative (-) wire and positive (+) wire.

3. How serious is the U0009 OBDII code in a Mercury vehicle?

- The U0009 code should be addressed promptly as it can disrupt communication between vital control modules, leading to potential safety concerns and performance issues in the vehicle.

4. Can I drive my Mercury with the U0009 trouble code present?

- It is not recommended to drive the vehicle with the U0009 code active, as it may result in sporadic electronic malfunctions and compromise the overall performance and safety of the vehicle.

5. How do I diagnose and repair the U0009 code in my Mercury?

- Diagnosing and repairing the U0009 code usually involves inspecting the wiring harness for any visible damage, checking the connectors for corrosion or loose connections, and using a multimeter to test the resistance between the CAN bus wires.

6. What are some tips for preventing the U0009 code from recurring in my Mercury?

- To prevent the U0009 code from reoccurring, it is important to ensure proper wire routing, secure connections, and regular maintenance to avoid any damage to the high-speed CAN communication bus wiring.

7. Can a DIY enthusiast fix the U0009 code issue in a Mercury, or is professional help necessary?

- While some DIY enthusiasts may have the skills to address the U0009 code, it is recommended to seek professional help, especially when dealing with intricate electrical systems to ensure proper diagnosis and repair.

8. Is the U0009 code a common issue in Mercury vehicles?

- The U0009 code related to the high-speed CAN communication bus short circuit is not extremely common but can occur in Mercury vehicles, especially those with complex electronic systems.

9. How long does it typically take to repair the U0009 code in a Mercury at a repair shop?

- The time needed to repair the U0009 code can vary depending on the extent of the wiring damage and the expertise of the technician, but it may take a few hours to a day at a repair shop.

10. Are there any recalls or technical service bulletins related to the U0009 code in Mercury vehicles?

- It is recommended to check with your local Mercury dealership or visit the National Highway Traffic Safety Administration (NHTSA) website for any recalls or technical service bulletins related to the U0009 code in your specific Mercury model.