U179A 2018 GMC Sierra Code - Lost Communication with Hybrid/EV Powertrain Control Module 2
Quick Answer
The serial data circuit is the means by which the devices in the vehicle communicate with each other. Common causes include Faulty Hybrid/EV Powertrain Control Module 2, Hybrid/EV Powertrain Control Module 2 harness is open or shorted, Hybrid/EV Powertrain Control Module 2 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
- U179A 2018 GMC Sierra indicates Lost Communication with Hybrid/EV Powertrain Control Module 2.
- Common causes
- Common causes include Faulty Hybrid/EV Powertrain Control Module 2, Hybrid/EV Powertrain Control Module 2 harness is open or shorted, Hybrid/EV Powertrain Control Module 2 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 U179A 2018 GMC Sierra Description
What are the Possible Causes of the DTC U179A 2018 GMC Sierra?
- Faulty Hybrid/EV Powertrain Control Module 2
- Hybrid/EV Powertrain Control Module 2 harness is open or shorted
- Hybrid/EV Powertrain Control Module 2 circuit poor electrical connection
How to Fix the DTC U179A 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 U179A 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 U179A 2018 GMC Sierra code?
Need more information on how to fix the U179A 2018 GMC Sierra code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the U179A 2018 GMC Sierra code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about U179A 2018 GMC Sierra Code
1. What does the OBDII code U179A mean on a 2018 GMC Sierra?
The U179A code indicates "Lost Communication with Hybrid/EV Powertrain Control Module 2," meaning the vehicle's systems cannot communicate with the secondary powertrain control module.
2. What are the common symptoms of code U179A in a GMC Sierra?
Symptoms may include a check engine light, erratic engine or transmission behavior, reduced power mode, or issues with hybrid/EV system performance.
3. What causes the U179A code to appear in a 2018 GMC Sierra?
Common causes include faulty wiring or connectors, a malfunctioning Hybrid/EV Powertrain Control Module 2, software issues, or a communication bus failure.
4. Can a weak battery trigger the U179A code?
Yes, a weak or failing 12V battery can cause communication errors, including the U179A code, as proper voltage is needed for module communication.
5. How can I diagnose the U179A code on my GMC Sierra?
Diagnose by checking for damaged wiring or loose connections at the Hybrid/EV Powertrain Control Module 2, inspecting the CAN bus network, and using a scan tool to monitor communication.
6. Is it safe to drive with the U179A code active?
It is not recommended to drive with this code active, as it can lead to reduced functionality or failure of the hybrid/EV powertrain system.
7. How much does it cost to fix the U179A code?
Repair costs can vary widely depending on the issue but may range from $100 for wiring repairs to over $1,000 if the control module needs replacement.
8. Can updating the vehicle’s software resolve the U179A code?
Yes, in some cases, a software update or reprogramming of the powertrain control module can resolve communication issues.
9. What tools are needed to fix the U179A code?
You’ll need an advanced scan tool capable of reading and diagnosing communication faults, as well as basic tools to inspect wiring and connectors.
10. Can a short circuit cause the U179A code?
Yes, a short circuit in the wiring harness or connectors can disrupt communication and trigger the U179A code.
Discuss the causes and fixes for U179A 2018 GMC Sierra OBDII Code
Code U179A 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.
