AutoCodes – Generic – U0239

U0239 Code - Lost Communication With Entrapment 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 Entrapment Control Module 'A', Entrapment Control Module 'A' harness is open or shorted, Entrapment 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: U0239 indicates Lost Communication With Entrapment Control Module 'A'.
Common causes: Common causes include Faulty Entrapment Control Module 'A', Entrapment Control Module 'A' harness is open or shorted, Entrapment 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.

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Code Popularity 2,785

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 04, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U0239 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 Entrapment Control Module 'A' has not been received.

OBDII Code U0239 - Lost Communication With Entrapment Control Module 'A' - AutoCodes.com — U0239 Code - Lost Communication With Entrapment Control Module 'A'

What does this mean?

What are the Possible Causes of the DTC U0239?

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

How to Fix the DTC U0239?

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 U0239 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 U0239 code?

Need more information on how to fix the U0239 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U0239 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 U0239 Code

1. What are the common symptoms of OBDII code U0239?

The common symptoms of U0239 include the illumination of the Check Engine Light (CEL), difficulty starting the vehicle, and issues with the automatic door locks.

2. What can cause the OBDII code U0239 to be triggered?

The U0239 code is typically triggered by a communication failure between the vehicle's onboard computer and the Entrapment Control Module 'A'.

3. How serious is the U0239 code?

While the U0239 code itself may not directly affect the drivability of the vehicle, it is important to address communication issues promptly to prevent potential safety hazards related to the Entrapment Control Module.

4. How can I diagnose the U0239 code?

Diagnosing the U0239 code usually involves using a diagnostic scanner to retrieve the code, checking for any other related codes, and testing the communication between the modules.

5. What are some repair tips for fixing the U0239 code?

Repair tips for U0239 may include checking the wiring and connections related to the Entrapment Control Module 'A', resetting the codes and retesting the system, and replacing the module if necessary.

6. Can I drive my vehicle with the U0239 code?

It is generally not recommended to drive the vehicle with an unresolved U0239 code, as it may lead to further communication failures or safety issues related to the Entrapment Control Module.

7. How much does it cost to repair the U0239 code?

The cost of repairing the U0239 code can vary depending on the underlying cause, the need for parts replacement, and labor costs. It is advisable to consult a mechanic for a more accurate estimate.

8. Can the U0239 code be fixed at home?

While some DIY enthusiasts may attempt to diagnose and fix the U0239 code at home, it is recommended to have a professional mechanic address communication issues to ensure proper repairs and safety.

9. Are there any recalls related to the U0239 code?

Recalls related to the U0239 code may vary depending on the vehicle make and model. It is advisable to check with the manufacturer or authorized service centers for any related recalls.

10. How can I prevent the U0239 code from recurring?

Regular maintenance, checking the vehicle's electrical system, and addressing any communication issues promptly can help prevent the U0239 code from recurring in the future.