AutoCodes – GMC – P150C 2015 GMC Sierra

P150C 2015 GMC Sierra Code - Transmission Control Module Engine Speed Request Signal Message Counter Incorrect

Quick Answer

To improve vehicle shift, and feel, the Transmission Control Module (TCM) is constantly sending the Engine Control Module (ECM) serial data messages with information regarding its request for modifying engine speed or torque. 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: P150C 2015 GMC Sierra indicates Transmission Control Module Engine Speed Request 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.

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Code Popularity 180

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 P150C 2015 GMC Sierra Description

To improve vehicle shift, and feel, the Transmission Control Module (TCM) is constantly sending the Engine Control Module (ECM) serial data messages with information regarding its request for modifying engine speed or torque. The ECM sets this code when it detects a discrepancy in the structure of this message causing its integrity to be questioned. An intermittent fault in the Controller Area Network (CAN) circuits will cause Diagnostic Trouble Code (DTC) P150C to set.

OBDII Code P150C 2015 GMC Sierra - Transmission Control Module Engine Speed Request Signal Message Counter Incorrect - AutoCodes.com — P150C 2015 GMC Sierra Code - Transmission Control Module Engine Speed Request Signal Message Counter Incorrect

What does this mean?

What are the Possible Causes of the DTC P150C 2015 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 P150C 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 P150C 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 P150C 2015 GMC Sierra code?

Need more information on how to fix the P150C 2015 GMC Sierra code? Get Access to Factory Service Manuals

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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 P150C 2015 GMC Sierra Code

1. What does the OBDII code P150C mean in a 2015 GMC Sierra?

P150C indicates an issue where the Transmission Control Module (TCM) detects an incorrect engine speed request signal message counter from the Engine Control Module (ECM).

2. What are the common symptoms of code P150C in a 2015 GMC Sierra?

Symptoms may include reduced engine performance, transmission shifting issues, a lit Check Engine Light, or the vehicle entering limp mode.

3. What causes the P150C code to appear in a 2015 GMC Sierra?

Common causes include a faulty TCM, ECM communication issues, damaged wiring or connectors, or software/calibration problems in the control modules.

4. Can I drive my 2015 GMC Sierra with the P150C code?

Driving with this code is not recommended as it may lead to reduced performance, compromised shifting, or further transmission and engine control issues.

5. How is the P150C code diagnosed in a 2015 GMC Sierra?

Diagnosis involves scanning the vehicle with an OBDII tool, checking for communication errors between the ECM and TCM, inspecting wiring and connectors, and verifying module software compatibility.

6. How can I fix the P150C code on my 2015 GMC Sierra?

Repairs may include updating or reprogramming the ECM or TCM software, repairing or replacing damaged wiring, or replacing a faulty control module.

7. Is the P150C code specific to the 2015 GMC Sierra?

While P150C is common in GM vehicles, its exact meaning and troubleshooting steps may vary slightly across models and years.

8. Will clearing the P150C code fix the problem in my 2015 GMC Sierra?

Clearing the code without addressing the root cause is only a temporary solution, as the issue will likely return until resolved.

9. How much does it cost to repair the P150C code on a 2015 GMC Sierra?

Repair costs vary depending on the root cause but may range from $100 for minor wiring repairs to $1,000 or more for module replacement and reprogramming.

10. Can a bad battery cause the P150C code in a 2015 GMC Sierra?

Yes, a weak or failing battery can cause voltage fluctuations, potentially leading to communication errors between the ECM and TCM.