AutoCodes – Generic – U0068

U0068 Code - Vehicle Communication Bus 'E' (+) High

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: U0068 indicates Vehicle Communication Bus 'E' (+) High.
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 2,993

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 U0068 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 U0068 - Vehicle Communication Bus 'E' (+) High - AutoCodes.com — U0068 Code - Vehicle Communication Bus 'E' (+) High

What does this mean?

What are the Possible Causes of the DTC U0068?

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 U0068?

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 U0068 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 U0068 code?

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Need Help with the Code?

Get the U0068 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 U0068 Code

What does the OBDII code U0068 mean?

Code U0068 indicates that there is a high voltage issue with the Vehicle Communication Bus 'E' (+), which is part of the vehicle's communication network.

What are the common symptoms of code U0068?

Symptoms may include warning lights on the dashboard, intermittent communication issues between modules, and difficulty diagnosing or clearing other codes.

What causes the U0068 code?

Common causes include damaged wiring, loose or corroded connectors, a short circuit, or a malfunctioning control module.

Can code U0068 affect vehicle performance?

Yes, it can impact vehicle performance by disrupting communication between critical systems like the engine, transmission, or safety modules.

How can I diagnose the U0068 code?

Start by inspecting the wiring and connectors related to the communication bus for damage or corrosion. Use a scan tool to check for other related codes or communication errors.

Can a weak battery contribute to code U0068?

Yes, a weak or failing battery may cause voltage irregularities, potentially triggering communication bus issues like U0068.

What tools are needed to repair code U0068?

You may need a digital multimeter, an OBDII scan tool, and wiring diagrams to trace and test the affected circuits and connectors.

Should I clear the U0068 code after repairs?

Yes, once repairs are completed, clear the code with a scan tool and monitor the system to ensure the issue is resolved.

Can code U0068 be caused by aftermarket modifications?

Yes, improperly installed aftermarket devices can interfere with the vehicleâ€™s communication bus and cause this code.

Is it safe to drive with code U0068 present?

While it may be possible to drive, it is not recommended as the code can lead to communication errors that affect critical systems, potentially compromising safety.