AutoCodes – GMC – P143B 2015 GMC Sierra

P143B 2015 GMC Sierra Code - Reductant Control System Information Signal Message Counter Incorrect

Quick Answer

Control modules connected to the serial data circuits monitor the communication during normal vehicle operation. Common causes include Faulty Reductant Control System. 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: P143B 2015 GMC Sierra indicates Reductant Control System Information Signal Message Counter Incorrect.
Common causes: Common causes include Faulty Reductant Control System.
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 136

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 Sep 28, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P143B 2015 GMC Sierra Description

Control modules connected to the serial data circuits monitor the communication during normal vehicle operation. Operating information and commands are exchanged among the control modules. Each module on the serial data circuit maintains a transmit error counter and a receive error counter. The counter values increase with detected errors and decrease with error-free messages. The Diagnostic Trouble Code (DTC) will be set when the Reductant Control System Information Signal Message Counter is Incorrect.

OBDII Code P143B 2015 GMC Sierra - Reductant Control System Information Signal Message Counter Incorrect - AutoCodes.com — P143B 2015 GMC Sierra Code - Reductant Control System Information Signal Message Counter Incorrect

What does this mean?

What are the Possible Causes of the DTC P143B 2015 GMC Sierra?

Faulty Reductant Control System

How to Fix the DTC P143B 2015 GMC Sierra?

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 P143B 2015 GMC Sierra 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 P143B 2015 GMC Sierra code?

Need more information on how to fix the P143B 2015 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

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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 P143B 2015 GMC Sierra Code

1. What does the OBDII code P143B mean on a 2015 GMC Sierra?

The P143B code indicates an issue with the Reductant Control System, specifically that the Information Signal Message Counter is incorrect or out of sequence.

2. What are the symptoms of the P143B code in a 2015 GMC Sierra?

Common symptoms include the check engine light turning on, possible DEF (Diesel Exhaust Fluid) system warnings, reduced engine performance, or limited vehicle speed.

3. What causes the P143B code to appear on a 2015 GMC Sierra?

The code can be caused by faulty wiring or connectors in the reductant control system, a malfunctioning reductant control module, or corrupted communication data between modules.

4. How is the P143B code diagnosed in a 2015 GMC Sierra?

Technicians use an OBDII scanner to retrieve the code, inspect the wiring and connectors in the reductant system, and check for proper communication between the ECM and the reductant control module.

5. Can I drive my 2015 GMC Sierra with the P143B code?

Driving with this code may be possible, but it could lead to reduced performance or even DEF system failure, which may trigger a speed restriction if not addressed.

6. How do I fix the P143B code on a 2015 GMC Sierra?

Repairs may include inspecting and repairing damaged wiring or connectors, reprogramming or replacing the reductant control module, and ensuring all related modules are functioning properly.

7. Does the P143B code mean I need to replace the reductant control module?

Not necessarily. The issue could be due to wiring or communication problems rather than a faulty module. Proper diagnostics are required before replacing any components.

8. What tools are needed to diagnose the P143B code on a 2015 GMC Sierra?

An OBDII scanner with advanced diagnostics, a multimeter for checking electrical circuits, and possibly GM-specific diagnostic software to test module communication are needed.

9. How much does it cost to fix the P143B code on a 2015 GMC Sierra?

Repair costs vary depending on the issue, but wiring repairs may cost around $100-$300, while module replacement or reprogramming can exceed $500.

10. Can a software update resolve the P143B code on a 2015 GMC Sierra?

In some cases, a software update for the ECM or reductant control module can resolve communication issues and clear the code. Consult a dealership or authorized technician.