AutoCodes – GMC – P1631 2016 GMC Sierra

P1631 2016 GMC Sierra Code - Theft Deterrent Start Enable Signal Not Correct

Quick Answer

The Body Control Module (BCM) sends the pre-release information to the Engine Control Module (ECM) via the serial data circuit. Common causes include Perform security relearn procedure, Faulty Ignition switch assembly, Ignition switch assembly harness is open or shorted. 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: P1631 2016 GMC Sierra indicates Theft Deterrent Start Enable Signal Not Correct.
Common causes: Common causes include Perform security relearn procedure, Faulty Ignition switch assembly, Ignition switch assembly harness is open or shorted.
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 269

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 Aug 17, 2022

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P1631 2016 GMC Sierra Description

The Body Control Module (BCM) sends the pre-release information to the Engine Control Module (ECM) via the serial data circuit. The ECM then sends a challenge to the BCM. Both the ECM and BCM perform a calculation on this challenge. If the calculated response from the BCM equals the calculation performed by the ECM, the ECM will allow the vehicle to start. The BCM follows this action by sending the remaining immobilizer data to the ECM. If the immobilizer data sent by the BCM matches that stored by the ECM, the ECM will allow the engine to remain running. The Diagnostic Trouble Code (DTC) will be set if the ECM receives incorrect immobilizer data from the BCM.

OBDII Code P1631 2016 GMC Sierra - Theft Deterrent Start Enable Signal Not Correct - AutoCodes.com — P1631 2016 GMC Sierra Code - Theft Deterrent Start Enable Signal Not Correct

What does this mean?

What are the Possible Causes of the DTC P1631 2016 GMC Sierra?

Perform security relearn procedure
Faulty Ignition switch assembly
Ignition switch assembly harness is open or shorted
Ignition switch assembly circuit poor electrical connection

How to Fix the DTC P1631 2016 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 does this mean?

Code Tech Notes

Security Relearn Procedure:

-Insert the key, attempt to start the vehicle, and leave the key in the ON position.
In some vehicles, the Battery and Security light will blink for several seconds, and then shut off. Then the Security light will then remain ON. Leave the ignition ON until the Security light goes OFF. This will take more than 5 mins.
-When the Security light goes OFF, turn the ignition to the OFF position.
-Leave ignition OFF for 20 Seconds.
-Attempt to start the vehicle again and leave the key in the ON position.
-In some vehicles, the Battery and Security light will blink for several seconds, and then shut off. Then the Security light will then remain ON. Leave the ignition ON until the Security light goes OFF. This will take more than 5 mins.
-Turn the ignition to the OFF position for 20 Seconds.
-Attempt to start the vehicle again and leave the key in the ON position.
-In some vehicles, the Battery and Security light will blink for several seconds, and then shut off. Then the Security light will then remain ON. Leave the ignition ON until the Security light goes OFF. This will take more than 5 mins.
-Once this entire procedure has been completed (three times) your vehicle will start on the fourth attempt.

Note: Some vehicles perform the relearn in a different sequence. You may notice your security light, battery light, and abs light will alternate. Once the security light is left out of the sequence that is considered one step. Repeat the procedure two more times and on the fourth time, your vehicle will start.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1631 2016 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.

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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 P1631 2016 GMC Sierra Code

1. What does OBDII code P1631 on a 2016 GMC Sierra mean?

The code P1631 indicates that the Theft Deterrent Start Enable Signal is not correct, potentially preventing the vehicle from starting.

2. What are the common symptoms of OBDII code P1631 on a 2016 GMC Sierra?

Common symptoms include the engine cranking but not starting, the security light flashing on the dashboard, and the vehicle going into anti-theft mode.

3. What are the possible causes of OBDII code P1631 on a 2016 GMC Sierra?

Possible causes include a faulty ignition key, issues with the ignition lock cylinder, a malfunctioning ignition switch, or problems with the vehicle's immobilizer system.

4. How can I diagnose OBDII code P1631 on a 2016 GMC Sierra?

Diagnosing this code typically involves checking the key for damage, ensuring it is the correct key for the vehicle, inspecting the ignition lock cylinder, and scanning the vehicle's computer for related trouble codes.

5. Can I still drive my 2016 GMC Sierra with OBDII code P1631 present?

If the vehicle is in anti-theft mode due to this code, it may not start or operate properly. It is recommended to address the issue before attempting to drive the vehicle.

6. How can I repair OBDII code P1631 on a 2016 GMC Sierra?

Repair options may include reprogramming the key, replacing a faulty key, repairing or replacing the ignition lock cylinder, or addressing any issues with the vehicle's immobilizer system.

7. Can I reset OBDII code P1631 on a 2016 GMC Sierra by disconnecting the battery?

While disconnecting the battery may clear some trouble codes temporarily, it is not a guaranteed fix for this specific issue. It's best to diagnose and address the root cause of the code.

8. Are there any DIY tips for troubleshooting OBDII code P1631 on a 2016 GMC Sierra?

DIY tips may include checking the key for visible damage, ensuring it is the correct key for the vehicle, and inspecting the ignition components for any obvious issues before seeking professional help.

9. How much does it cost to fix OBDII code P1631 on a 2016 GMC Sierra?

The cost of fixing this code can vary depending on the root cause of the issue, the needed repairs or replacements, and labor costs. It is advisable to consult a mechanic for a more accurate estimate.

10. Will OBDII code P1631 on a 2016 GMC Sierra affect the vehicle's performance?

If left unresolved, this code can prevent the vehicle from starting or operating properly, impacting its performance. It is important to address the issue promptly to avoid further complications.