AutoCodes – Lexus – U0142 Lexus

U0142 Lexus Code - Lost Communication with Body Control Module 'B'

Quick Answer

The Controller Area Network (CAN) is a standard bus system in vehicles that enables the connection of automotive devices without the need for a host computer. Common causes include Faulty Controller Area Network (CAN) Communication System, Faulty Body Control Module 'B', Body Control Module 'B' harness is open or shorted. 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: U0142 Lexus indicates Lost Communication with Body Control Module 'B'.
Common causes: Common causes include Faulty Controller Area Network (CAN) Communication System, Faulty Body Control Module 'B', Body Control Module 'B' harness is open or shorted.
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 1,275

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 27, 2023

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code U0142 Lexus Description

The Controller Area Network (CAN) is a standard bus system in vehicles that enables the connection of automotive devices without the need for a host computer. The exchange of operating information and commands among devices is facilitated by pre-programmed information about the required message exchange on the serial data circuits. Communication is carried out using two dedicated wires, known as CAN high and CAN low, with both lines carrying 2.5V when the CAN bus is in idle mode. During the transmission of data bits, the CAN high line increases to 3.75V while the CAN low drops to 1.25V, creating 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 Body Control Module 'B' has not been received.

OBDII Code U0142 Lexus - Lost Communication with Body Control Module 'B' - AutoCodes.com — U0142 Lexus Code - Lost Communication with Body Control Module 'B'

What does this mean?

What are the Possible Causes of the DTC U0142 Lexus?

Faulty Controller Area Network (CAN) Communication System
Faulty Body Control Module 'B'
Body Control Module 'B' harness is open or shorted
Body Control Module 'B' circuit poor electrical connection

How to Fix the DTC U0142 Lexus?

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 does this mean?

Code Tech Notes

When there are problems with the way different systems in a vehicle communicate with each other using a technology called Controller Area Network (CAN) communication, Diagnostic Trouble Codes (DTC) are displayed. These codes can be caused by issues with the main bus or branch of the communication network, or with the Electronic Control Units (ECUs) and sensors that make up the different systems. If you see code for both the CAN communication problems and internal or power source problems at the same time, you should focus on fixing the internal or power source problems first.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the U0142 Lexus 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.

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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 U0142 Lexus Code

1. What are the common symptoms of OBDII code U0142 in a Lexus indicating a lost communication with the Body Control Module 'B'?

- Common symptoms include issues with power windows, door locks, interior lights, and other body control functions.

2. What are the possible causes of the U0142 code in a Lexus?

- The U0142 code can be caused by a faulty Body Control Module 'B', wiring issues, a blown fuse, or a poor connection.

3. How can I diagnose the U0142 code in my Lexus?

- Diagnosis typically involves checking the wiring connections to the Body Control Module 'B', inspecting fuses, and using a diagnostic scanner to communicate with the module.

4. Can I still drive my Lexus with the U0142 code present?

- It is not recommended to drive your Lexus with the U0142 code present, as it may affect critical body control functions and lead to potential safety hazards.

5. How can I repair the U0142 code in my Lexus?

- Repairing the U0142 code often involves addressing the underlying issue causing the communication loss, such as replacing the Body Control Module 'B' or repairing wiring faults.

6. Is it possible to reset the U0142 code in a Lexus without fixing the issue?

- While you can clear the code with a diagnostic scanner, it is crucial to address the root cause to prevent the code from reoccurring.

7. Are there any common DIY fixes for the U0142 code in a Lexus?

- DIY fixes may include checking and securing wiring connections, inspecting fuses, and ensuring proper grounding of the Body Control Module 'B'.

8. How much does it typically cost to repair the U0142 code in a Lexus?

- Repair costs for the U0142 code can vary depending on the specific issue, but it may range from a few hundred to a few thousand dollars, including parts and labor.

9. Can a mechanic help with diagnosing and repairing the U0142 code in my Lexus?

- Yes, a qualified mechanic with experience in automotive electronics can diagnose and repair the U0142 code in your Lexus efficiently and effectively.

10. How can I prevent the U0142 code from occurring again in my Lexus?

- Regular maintenance, checking electrical connections, and addressing any warning signs promptly can help prevent the U0142 code from occurring again in your Lexus.