AutoCodes – Generic – U2142

U2142 Code - Lost Communication With UART System

Quick Answer

Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Faulty Universal Asynchronous Receiver Transmitter (UART), Universal Asynchronous Receiver Transmitter harness is open or shorted, Universal Asynchronous Receiver Transmitter 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: U2142 indicates Lost Communication With UART System.
Common causes: Common causes include Faulty Universal Asynchronous Receiver Transmitter (UART), Universal Asynchronous Receiver Transmitter harness is open or shorted, Universal Asynchronous Receiver Transmitter 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 5,727

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 Jun 16, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U2142 Description

Devices connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the devices. The devices have prerecorded information about what messages are needed to be exchanged on the serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used by the receiver device as an availability indication of the transmitter device. Each message contains the identification number of the transmitter device. A loss of serial data communications Diagnostic Trouble Code (DTC) does not represent a failure of the devices that contain the stored code. The DTC will set when a supervised periodic message that includes the transmitter device availability has not been received.

OBDII Code U2142 - Lost Communication With UART System - AutoCodes.com — U2142 Code - Lost Communication With UART System

What does this mean?

What are the Possible Causes of the DTC U2142?

Faulty Universal Asynchronous Receiver Transmitter (UART)
Universal Asynchronous Receiver Transmitter harness is open or shorted
Universal Asynchronous Receiver Transmitter circuit poor electrical connection

How to Fix the DTC U2142?

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 U2142 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 U2142 code?

Need more information on how to fix the U2142 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the U2142 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

U2142 Buick — Lost Communication With UART System
U2142 Cadillac — Lost Communication With UART System
U2142 Chevrolet — Lost Communication With UART System
U2142 GMC — Lost Communication With UART System
U2142 Pontiac — Lost Communication With UART System

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 U2142 Code

What does the OBDII code U2142 mean?

The OBDII code U2142 indicates a "Lost Communication With UART System," which signifies that the vehicle's diagnostic system has detected a failure in communication with a specific module or component.

What are common symptoms of the U2142 code?

Common symptoms may include warning lights on the dashboard, such as the Check Engine Light, malfunctioning vehicle systems related to the affected module, and intermittent or complete loss of function in certain electronic features.

What could cause the U2142 code?

Possible causes include faulty wiring or connections, a malfunctioning control module, issues with the UART communication protocol, or software glitches within the vehicle's electronic systems.

How can I diagnose the U2142 code?

To diagnose the U2142 code, use an OBDII scanner to confirm the code and check for any related codes. Inspect the wiring and connectors for damage, and test the affected module for proper operation.

Can I drive my car with the U2142 code?

While it may be possible to drive the vehicle, it is not recommended, as the lost communication can affect critical systems, leading to safety issues or further damage.

What are some repair tips for the U2142 code?

Repair tips include checking and repairing any damaged wiring or connectors related to the affected module, updating or reprogramming the control module software, and replacing any faulty components.

Is U2142 a serious code?

Yes, U2142 can be serious, as it indicates a communication failure that may affect the operation of essential vehicle systems, potentially leading to further issues if not addressed.

How can I prevent the U2142 code from recurring?

To prevent the U2142 code from recurring, regularly inspect and maintain the vehicle's electrical system, ensure all connections are secure, and keep the software of control modules updated.

Can a professional mechanic help with the U2142 code?

Yes, a professional mechanic can provide a thorough diagnosis and repair for the U2142 code, using specialized tools and knowledge to address the underlying issues effectively.