AutoCodes – GMC – P27A7 2017 GMC Sierra

P27A7 2017 GMC Sierra Code - Transmission Control Solenoid Valve 1 Calibration Incorrect

Quick Answer

The Transmission Control Solenoid Valve 1, 2, 3, 4, 5, 6, 7 have a unique current versus oil pressure characteristic that is used to properly upshift or downshift the transmission. Common causes include Solenoid Valve Characterization Reprogramming. 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: P27A7 2017 GMC Sierra indicates Transmission Control Solenoid Valve 1 Calibration Incorrect.
Common causes: Common causes include Solenoid Valve Characterization Reprogramming.
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 179

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 22, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P27A7 2017 GMC Sierra Description

The Transmission Control Solenoid Valve 1, 2, 3, 4, 5, 6, 7 have a unique current versus oil pressure characteristic that is used to properly upshift or downshift the transmission. The data for each solenoid valve is programmed into the Transmission Control Module (TCM). The Diagnostic Trouble Code (DTC) will be set when the Transmission Control Solenoid Valve Calibration Data has not been programmed.

OBDII Code P27A7 2017 GMC Sierra - Transmission Control Solenoid Valve 1 Calibration Incorrect - AutoCodes.com — P27A7 2017 GMC Sierra Code - Transmission Control Solenoid Valve 1 Calibration Incorrect

What does this mean?

What are the Possible Causes of the DTC P27A7 2017 GMC Sierra?

Solenoid Valve Characterization Reprogramming

How to Fix the DTC P27A7 2017 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 P27A7 2017 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 P27A7 2017 GMC Sierra code?

Need more information on how to fix the P27A7 2017 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P27A7 2017 GMC Sierra 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 P27A7 2017 GMC Sierra Code

1. What does the OBDII code P27A7 mean on a 2017 GMC Sierra?

The P27A7 code indicates that the Transmission Control Solenoid Valve 1 Calibration is incorrect, meaning there is an issue with the calibration or performance of Solenoid Valve 1 in the transmission system.

2. What are the common symptoms of the P27A7 code in a 2017 GMC Sierra?

Symptoms may include rough or erratic shifting, transmission slipping, delayed gear engagement, or the Check Engine Light illuminating.

3. What causes the P27A7 code to appear in a 2017 GMC Sierra?

Common causes include software calibration issues, a faulty transmission control solenoid, wiring problems, or a malfunction in the transmission control module (TCM).

4. Can I keep driving my 2017 GMC Sierra with the P27A7 code active?

While the vehicle may still be drivable, prolonged operation with this issue could cause further transmission damage. Itâ€™s best to address the issue as soon as possible.

5. How is the P27A7 code diagnosed in a 2017 GMC Sierra?

A technician will use a scan tool to verify the code, inspect the transmission wiring and connections, and test the performance of the solenoid. They may also check for software updates or calibration issues in the TCM.

6. What are the repair options for the P27A7 code on a 2017 GMC Sierra?

Repairs may involve reprogramming or updating the TCM software, replacing the faulty solenoid, repairing damaged wiring, or replacing the TCM if necessary.

7. How much does it cost to fix the P27A7 code on a 2017 GMC Sierra?

The cost varies depending on the exact issue but can range from $150 to $500 for recalibration or solenoid replacement. If the TCM needs replacement, costs may be higher.

8. Can a software update fix the P27A7 code on a 2017 GMC Sierra?

Yes, if the issue is related to outdated or incorrect calibration data in the TCM, a software update or reprogramming may resolve the problem.

9. What tools are needed to address the P27A7 code on a 2017 GMC Sierra?

A professional-grade OBDII scan tool, a multimeter for electrical testing, and potentially software for TCM reprogramming are typically required.

10. Is the P27A7 code a common issue in the 2017 GMC Sierra?

While not extremely common, it can occur in vehicles with transmission calibration or solenoid-related problems, especially if maintenance has been neglected.