AutoCodes – GMC – P12FC GMC

P12FC GMC Code - Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 2

Quick Answer

The cylinder deactivation exhaust flow control system consists of valves installed at the inlet of the muffler. Common causes include Faulty Cylinder Deactivation Exhaust Flow Valve, Cylinder Deactivation Exhaust Flow Valve harness is open or shorted, Cylinder Deactivation Exhaust Flow Valve 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: P12FC GMC indicates Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 2.
Common causes: Common causes include Faulty Cylinder Deactivation Exhaust Flow Valve, Cylinder Deactivation Exhaust Flow Valve harness is open or shorted, Cylinder Deactivation Exhaust Flow Valve 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 1,072

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 12, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P12FC GMC Description

The cylinder deactivation exhaust flow control system consists of valves installed at the inlet of the muffler. The exhaust flow control system is used to tune the exhaust note. The Powertrain Control Module (PCM) monitors the Cylinder Deactivation Exhaust Flow Valve. The PCM sets the OBDII code when the Cylinder Deactivation Exhaust Flow Valve is not to factory specifications.

OBDII Code P12FC GMC - Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 2 - AutoCodes.com — P12FC GMC Code - Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 2

What does this mean?

What are the Possible Causes of the DTC P12FC GMC?

Faulty Cylinder Deactivation Exhaust Flow Valve
Cylinder Deactivation Exhaust Flow Valve harness is open or shorted
Cylinder Deactivation Exhaust Flow Valve circuit poor electrical connection

How to Fix the DTC P12FC GMC?

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 P12FC GMC 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 P12FC GMC code?

Need more information on how to fix the P12FC GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P12FC GMC code diagnosed by a professional: Find a repair shop in your area

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 P12FC GMC Code

1. What are common symptoms of OBDII code P12FC GMC?

- Common symptoms include poor engine performance, reduced fuel efficiency, rough idling, and illuminated Check Engine Light.

2. What does the OBDII code P12FC GMC indicate?

- The code indicates that the exhaust flow valve in Bank 2, related to cylinder deactivation, is stuck closed.

3. What are the possible causes of the Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 2 code?

- Possible causes include a faulty exhaust flow valve, wiring issues, a malfunctioning solenoid, or a problem with the cylinder deactivation system.

4. How can I diagnose the issue related to code P12FC GMC?

- Diagnose by checking the exhaust flow valve operation, inspecting the wiring and connections, and using a scan tool to monitor the cylinder deactivation system.

5. Can I drive my vehicle with the P12FC GMC code present?

- It is not recommended to drive with this code present, as it can lead to further damage and reduced engine performance.

6. How can I repair the Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 2 issue?

- Repair methods may include replacing the faulty exhaust flow valve, repairing any wiring issues, or addressing problems with the cylinder deactivation system.

7. Are there any temporary fixes for the P12FC GMC code?

- Temporary fixes like clearing the code with a scan tool may temporarily resolve the Check Engine Light, but the underlying issue should still be addressed.

8. How much does it typically cost to repair the Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 2 problem?

- Repair costs can vary depending on the specific issue, but expect to pay for parts and labor, which can range from a few hundred to over a thousand dollars.

9. Can a DIY enthusiast fix the P12FC GMC code at home?

- Depending on your skill level and access to tools, some DIY enthusiasts may be able to address the issue, but it is recommended to consult a professional for accurate diagnosis and repair.

10. How long does it usually take to repair the Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 2 issue?

- The repair time can vary based on the extent of the problem and the availability of parts, but it typically takes a few hours to a day to complete the repairs.