P179B 2018 GMC Sierra Code - Transmission Range State Command 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 Transmission Control Module (TCM), Transmission Control Module harness is open or shorted, Transmission Control Module 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
- P179B 2018 GMC Sierra indicates Transmission Range State Command Signal Message Counter Incorrect.
- Common causes
- Common causes include Faulty Transmission Control Module (TCM), Transmission Control Module harness is open or shorted, Transmission Control Module 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.
Code P179B 2018 GMC Sierra Description
What are the Possible Causes of the DTC P179B 2018 GMC Sierra?
- Faulty Transmission Control Module (TCM)
- Transmission Control Module harness is open or shorted
- Transmission Control Module circuit poor electrical connection
How to Fix the DTC P179B 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 P179B 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 P179B 2018 GMC Sierra code?
Need more information on how to fix the P179B 2018 GMC Sierra code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P179B 2018 GMC Sierra code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P179B 2018 GMC Sierra Code
1. What does the OBDII code P179B mean on a 2018 GMC Sierra?
The code P179B indicates "Transmission Range State Command Signal Message Counter Incorrect," meaning there’s an issue with the communication between the transmission control module (TCM) and other vehicle systems.
2. What are the common symptoms of code P179B in a 2018 GMC Sierra?
Symptoms include erratic shifting, transmission slipping, delayed gear engagement, or the illumination of the check engine light.
3. What causes the P179B code in a 2018 GMC Sierra?
The code can be triggered by a faulty transmission control module (TCM), wiring issues, connector problems, or software glitches in the TCM.
4. Can driving with the P179B code damage my 2018 GMC Sierra?
Yes, prolonged driving with this code can cause further transmission damage and lead to unsafe driving conditions.
5. How is code P179B diagnosed in a 2018 GMC Sierra?
Diagnosis involves scanning the TCM for additional codes, inspecting wiring and connectors, and testing the communication signals between the modules.
6. What repairs can fix the P179B code in a 2018 GMC Sierra?
Repairs may include replacing the TCM, repairing damaged wiring or connectors, or updating the software in the control modules.
7. Can a faulty transmission control module cause the P179B code?
Yes, a malfunctioning TCM can disrupt communication signals and trigger this code.
8. How much does it cost to repair code P179B in a 2018 GMC Sierra?
Repair costs vary but can range from $300 to $1,000 depending on whether the issue involves wiring repairs or TCM replacement.
9. Can a weak battery cause the P179B code in a 2018 GMC Sierra?
While unlikely, a weak or failing battery can sometimes affect module communication and contribute to triggering this code.
10. Should I address the P179B code immediately in my 2018 GMC Sierra?
Yes, addressing the code promptly can prevent further transmission damage and ensure safe vehicle operation.
Discuss the causes and fixes for P179B 2018 GMC Sierra OBDII Code
Code P179B 2018 GMC Sierra comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
