AutoCodes – Generic – U0297

U0297 Code - Lost Communication With AC To DC Converter Control Module 'B'

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 AC To DC Converter Control Module 'B', AC To DC Converter Control Module 'B' harness is open or shorted, AC To DC Converter Control Module 'B' 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: U0297 indicates Lost Communication With AC To DC Converter Control Module 'B'.
Common causes: Common causes include Faulty AC To DC Converter Control Module 'B', AC To DC Converter Control Module 'B' harness is open or shorted, AC To DC Converter Control Module 'B' 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.

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Code Popularity 1,753

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 Apr 06, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U0297 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 AC To DC Converter Control Module 'B' has not been received.

OBDII Code U0297 - Lost Communication With AC To DC Converter Control Module 'B' - AutoCodes.com — U0297 Code - Lost Communication With AC To DC Converter Control Module 'B'

What does this mean?

What are the Possible Causes of the DTC U0297?

Faulty AC To DC Converter Control Module 'B'
AC To DC Converter Control Module 'B' harness is open or shorted
AC To DC Converter Control Module 'B' circuit poor electrical connection

How to Fix the DTC U0297?

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 U0297 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 U0297 code?

Need more information on how to fix the U0297 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U0297 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 U0297 Code

What does OBD-II code U0297 mean?

Code U0297 indicates a loss of communication between the vehicle’s primary controller and the AC to DC Converter Control Module 'B'.

What are the common symptoms of code U0297?

Symptoms may include a check engine light, reduced charging efficiency, or issues with hybrid or electric system functionality.

What causes code U0297 to appear?

Common causes include faulty wiring or connectors, a malfunctioning AC to DC Converter Control Module 'B', or software issues within the vehicle's control modules.

Can U0297 affect my vehicle’s performance?

Yes, this code can impact charging systems in hybrid or electric vehicles, potentially leading to reduced efficiency or system failure.

How do I diagnose code U0297?

Diagnose this code by inspecting wiring and connectors for damage, checking for module-specific faults, and using a diagnostic scanner to verify communication between modules.

Is U0297 specific to hybrid or electric vehicles?

Yes, this code typically appears in hybrid or electric vehicles as it relates to components that manage charging and energy conversion systems.

How can I fix code U0297?

To fix this code, repair or replace damaged wiring or connectors, update module software, or replace the AC to DC Converter Control Module 'B' if necessary.

Can I drive my car with code U0297?

While your car might still be drivable, ignoring this code may lead to further issues with the charging system or power management in hybrid or electric vehicles.

What tools do I need to troubleshoot code U0297?

You’ll need an OBD-II scanner with advanced capabilities, a multimeter to check electrical connections, and possibly manufacturer-specific service information.

Does code U0297 require professional repair?

In most cases, professional diagnosis and repair are recommended due to the complexity of the systems involved in hybrid or electric vehicles.