P143B 2018 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 2018 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.
Code P143B 2018 GMC Sierra Description
What are the Possible Causes of the DTC P143B 2018 GMC Sierra?
- Faulty Reductant Control System
How to Fix the DTC P143B 2018 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 2018 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 2018 GMC Sierra code?
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Frequently Asked Questions about P143B 2018 GMC Sierra Code
1. What does the OBDII code P143B mean on a 2018 GMC Sierra?
P143B indicates an issue with the Reductant Control System, specifically that the Information Signal Message Counter is incorrect, pointing to a communication error between modules.
2. What are the common symptoms of a P143B code?
Symptoms may include the check engine light or a service DEF (Diesel Exhaust Fluid) system warning, reduced engine performance, or trouble passing emissions tests.
3. What causes a P143B code to appear?
The code can be caused by issues such as faulty wiring or connectors, software glitches in the engine control module (ECM) or reductant control module, or a malfunctioning reductant system sensor.
4. Can a bad DEF sensor trigger the P143B code?
Yes, a malfunctioning DEF sensor within the reductant system can cause communication failures, leading to the P143B code.
5. How is the P143B code diagnosed?
A mechanic will use a scan tool to check for related codes, inspect wiring and connections in the reductant system, and verify communication between the ECM and reductant control module.
6. How can I fix the P143B code on my 2018 GMC Sierra?
Repairs may include updating the ECM software, repairing or replacing damaged wiring or connectors, or replacing a faulty sensor or reductant control module.
7. Is it safe to drive with a P143B code?
While the vehicle may still be drivable, ignoring the code can lead to reduced engine performance and potential DEF system failure, so it’s best to address the issue promptly.
8. Will clearing the P143B code with a scan tool fix the problem?
Clearing the code may temporarily remove the warning, but the underlying issue needs to be resolved to prevent the code from returning.
9. Can a low DEF fluid level cause the P143B code?
No, a low DEF level typically triggers different codes or warnings. The P143B code is related to communication errors in the reductant control system.
10. Does the P143B code require a software update to fix?
In some cases, updating the ECM or reductant control module software can resolve communication issues and fix the P143B code.
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