AutoCodes – GMC – P27AD 2017 GMC Sierra

P27AD 2017 GMC Sierra Code - Transmission Control Solenoid Valve 7 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: P27AD 2017 GMC Sierra indicates Transmission Control Solenoid Valve 7 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 319

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 P27AD 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 P27AD 2017 GMC Sierra - Transmission Control Solenoid Valve 7 Calibration Incorrect - AutoCodes.com — P27AD 2017 GMC Sierra Code - Transmission Control Solenoid Valve 7 Calibration Incorrect

What does this mean?

What are the Possible Causes of the DTC P27AD 2017 GMC Sierra?

Solenoid Valve Characterization Reprogramming

How to Fix the DTC P27AD 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 P27AD 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 P27AD 2017 GMC Sierra code?

Need more information on how to fix the P27AD 2017 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P27AD 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 P27AD 2017 GMC Sierra Code

1. What does the OBDII code P27AD mean on a 2017 GMC Sierra?

P27AD indicates that the Transmission Control Module (TCM) has detected an issue with the calibration of Solenoid Valve 7 in the transmission.

2. What are the common symptoms of the P27AD code?

Common symptoms include harsh or delayed shifting, transmission slipping, decreased fuel efficiency, and the check engine light being illuminated.

3. What causes the P27AD code to appear?

The code may be caused by a faulty transmission solenoid, outdated TCM software, damaged wiring or connectors, or internal transmission issues.

4. Can I drive my GMC Sierra with the P27AD code?

While the vehicle may still be operable, driving with this code can lead to further transmission damage and reduced performance. Itâ€™s best to address the issue promptly.

5. How is the P27AD code diagnosed?

A technician will typically use a scan tool to confirm the code, inspect the wiring and connectors for damage, and test the solenoid and TCM for proper operation.

6. How can the P27AD code be fixed?

Repairs may include reprogramming the TCM, replacing the faulty solenoid, repairing damaged wiring, or performing a transmission fluid flush if contamination is present.

7. Is a software update required to fix the P27AD code?

In some cases, a TCM software update may resolve calibration issues if no physical faults are present.

8. What does "Transmission Control Solenoid Valve 7 Calibration Incorrect" mean?

It means the TCM is detecting that Solenoid Valve 7 is not operating within its expected parameters, possibly due to incorrect calibration or a mechanical fault.

9. How much does it cost to fix the P27AD code?

Repair costs vary but typically range from $200 to $800, depending on whether the issue is electrical, software-related, or requires solenoid replacement.

10. Can low transmission fluid cause the P27AD code?

Yes, low or contaminated transmission fluid can cause solenoid calibration issues and trigger this code. Checking and replacing the fluid may help in some cases.