AutoCodes – Generic – U0111

U0111 Code - Lost Communication With Battery Energy Control Module 'A'

Quick Answer

A Controller Area Network (CAN) is a vehicle bus standard designed to interconnect automotive devices without a host computer. Common causes include Faulty Battery Energy Control Module 'A', Battery Energy Control Module 'A' harness is open or shorted, Battery Energy Control Module 'A' 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: U0111 indicates Lost Communication With Battery Energy Control Module 'A'.
Common causes: Common causes include Faulty Battery Energy Control Module 'A', Battery Energy Control Module 'A' harness is open or shorted, Battery Energy Control Module 'A' 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 30,091

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 30, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code U0111 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 periodic message from the Battery Energy Control Module 'A' has not been received.

OBDII Code U0111 - Lost Communication With Battery Energy Control Module 'A' - AutoCodes.com — U0111 Code - Lost Communication With Battery Energy Control Module 'A'

What does this mean?

What are the Possible Causes of the DTC U0111?

Faulty Battery Energy Control Module 'A'
Battery Energy Control Module 'A' harness is open or shorted
Battery Energy Control Module 'A' circuit poor electrical connection

How to Fix the DTC U0111?

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 U0111 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 U0111 code?

Need more information on how to fix the U0111 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U0111 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

U0111 Buick — Lost Communication With Battery Energy Control Module
U0111 Cadillac — Lost Communication With Battery Energy Control Module
U0111 Chevrolet — Lost Communication With Battery Energy Control Module
U0111 Ford — Lost Communication With Battery Energy Control Module 'A'
U0111 GMC — Lost Communication With Battery Energy Control Module
U0111 Lincoln — Lost Communication With Battery Energy Control Module 'A'
U0111 Mercury — Lost Communication With Battery Energy Control Module 'A'

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 U0111 Code

1. What does the OBDII code U0111 mean?

U0111 indicates a loss of communication with the Battery Energy Control Module 'A,' which monitors and manages the vehicle's battery system.

2. What are the common symptoms of code U0111?

Symptoms may include a lit check engine light, hybrid system warnings, poor fuel economy, reduced power, or the vehicle failing to start.

3. What causes the U0111 code to appear?

Common causes include faulty wiring or connectors, a malfunctioning Battery Energy Control Module, a failing CAN (Controller Area Network) bus, or power supply issues to the module.

4. Can I drive with the U0111 code active?

It is not recommended to drive with this code active, as it may affect the vehicle's battery management system, potentially leading to further damage or unsafe driving conditions.

5. How do I diagnose the U0111 code?

Start by inspecting the wiring and connectors for damage or corrosion, check the CAN bus for continuity, and verify the Battery Energy Control Module has proper power and ground connections.

6. Does the U0111 code mean the Battery Energy Control Module is faulty?

Not necessarily. While the module could be defective, the issue is often related to wiring, connectors, or network communication problems.

7. What tools are needed to troubleshoot the U0111 code?

A scan tool capable of reading manufacturer-specific codes and monitoring the CAN bus system, along with a multimeter, is typically required for diagnosis.

8. How much does it cost to fix the U0111 code?

Repair costs can vary widely depending on the root cause, ranging from $50 for minor wiring repairs to $1,000 or more if the Battery Energy Control Module needs replacement.

9. Can a dead vehicle battery cause the U0111 code?

Yes, a weak or dead vehicle battery can disrupt communication with the Battery Energy Control Module and trigger the U0111 code.

10. How can I prevent the U0111 code from recurring?

Regularly inspect and maintain the vehicleâ€™s electrical system, ensure all connections are secure and corrosion-free, and address battery issues promptly.