AutoCodes – Generic – U0055

U0055 Code - Vehicle Communication Bus 'D'

Quick Answer

A Controller Area Network (CAN) is a vehicle bus standard designed to interconnect automotive devices without a host computer. 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: U0055 indicates Vehicle Communication Bus 'D'.
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 16,448

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 U0055 Description

A Controller Area Network (CAN) is a vehicle bus standard designed to interconnect automotive devices without a host computer. Operating information and commands are exchanged among the devices. The devices have programmed information about what messages are needed to be exchanged on the serial data circuits. CAN bus uses two dedicated wires for communication. The wires are called CAN high and CAN low. When the CAN bus is in idle mode, both lines carry 2.5V. When data bits are being transmitted, the CAN high line goes to 3.75V, and the CAN low drops to 1.25V, thereby generating a 2.5V differential between the lines. Since communication relies on a voltage differential between the two bus lines, the CAN bus is NOT sensitive to inductive spikes, electrical fields, or other noise. The Diagnostic Trouble Code (DTC) sets when a supervised periodic message that includes the transmitter device availability has not been received.

OBDII Code U0055 - Vehicle Communication Bus 'D' - AutoCodes.com — U0055 Code - Vehicle Communication Bus 'D'

What does this mean?

What are the Possible Causes of the DTC U0055?

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 U0055?

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 U0055 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 U0055 code?

Need more information on how to fix the U0055 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U0055 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 U0055 Code

1. What are common symptoms of OBDII code U0055 (Vehicle Communication Bus 'D')?

- Common symptoms include issues with the vehicle's communication network, such as intermittent or complete loss of communication between control modules.

2. What are possible causes of OBDII code U0055?

- Possible causes include damaged wiring or connectors in the communication network, faulty control modules, or a malfunctioning communication bus.

3. How can I diagnose OBDII code U0055?

- Diagnosing U0055 typically involves using a diagnostic scanner to check for communication faults between control modules and inspecting the wiring and connectors for any damage.

4. Can OBDII code U0055 be triggered by a loose or disconnected connector?

- Yes, a loose or disconnected connector in the communication network can trigger U0055, causing communication issues between control modules.

5. What are some repair tips for resolving OBDII code U0055?

- Repair tips may include checking and repairing any damaged wiring or connectors, ensuring all connections are secure, and resetting the fault code to see if the issue persists.

6. Is it safe to continue driving with OBDII code U0055 present?

- It is generally not recommended to continue driving with U0055 present, as communication issues between control modules can affect the vehicle's performance and safety systems.

7. Can a DIY enthusiast repair OBDII code U0055 at home?

- Depending on the cause of U0055, DIY enthusiasts may be able to address the issue by checking and repairing wiring or connectors, but more complex repairs may require professional assistance.

8. How does OBDII code U0055 affect the vehicle's performance?

- U0055 can impact the vehicle's performance by causing communication failures between control modules, leading to potential issues with engine operation, transmission shifting, and other systems.

9. Are there any recalls or technical service bulletins related to OBDII code U0055?

- It's recommended to check with the vehicle manufacturer or a dealership for any recalls or technical service bulletins related to U0055, as some issues may be covered under warranty.

10. What should I do if OBDII code U0055 keeps coming back after repairs?

- If U0055 keeps reoccurring after repairs, it's advisable to conduct a thorough inspection of the communication network, control modules, and connectors to identify and address any underlying issues.