AutoCodes – GMC – P1649 2015 GMC Sierra

P1649 2015 GMC Sierra Code - Immobilizer Security Code Not Programmed

Quick Answer

When learning the security code, as well as the challenge and response sequence, the Engine Control Module (ECM) is placed in learn mode. Common causes include Perform Engine Control Module Immobilizer Learn Procedure, Faulty Engine Control Module (ECM), Engine Control Module 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: P1649 2015 GMC Sierra indicates Immobilizer Security Code Not Programmed.
Common causes: Common causes include Perform Engine Control Module Immobilizer Learn Procedure, Faulty Engine Control Module (ECM), Engine Control Module 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 166

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
Cost to Diagnose
FAQs
Comments
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Code P1649 2015 GMC Sierra Description

When learning the security code, as well as the challenge and response sequence, the Engine Control Module (ECM) is placed in learn mode. Once the security code and challenge/response are learned, learn mode will be exited when the engine is successfully started. The Diagnostic Trouble Code (DTC) will be set when the ECM has not learned a security code.

OBDII Code P1649 2015 GMC Sierra - Immobilizer Security Code Not Programmed - AutoCodes.com — P1649 2015 GMC Sierra Code - Immobilizer Security Code Not Programmed

What does this mean?

What are the Possible Causes of the DTC P1649 2015 GMC Sierra?

Perform Engine Control Module Immobilizer Learn Procedure
Faulty Engine Control Module (ECM)
Engine Control Module harness is open or shorted
Engine Control Module circuit poor electrical connection

How to Fix the DTC P1649 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 P1649 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 P1649 2015 GMC Sierra code?

Need more information on how to fix the P1649 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 P1649 2015 GMC Sierra Code

1. What are the common symptoms of OBDII code P1649 on a 2015 GMC Sierra?

- Common symptoms include difficulty starting the vehicle, the engine not turning over, and the security light staying illuminated.

2. What does the OBDII code P1649 on a 2015 GMC Sierra indicate?

- The code P1649 typically indicates that the immobilizer security code is not programmed or recognized by the vehicle's system.

3. What are the possible causes of OBDII code P1649 on a 2015 GMC Sierra?

- The main causes can be a faulty immobilizer system, a key with a transponder chip issue, or an issue with the vehicle's computer system.

4. How can I diagnose the OBDII code P1649 on my 2015 GMC Sierra?

- To diagnose this code, it is recommended to use a diagnostic scanner to read the code, check the immobilizer system, test the transponder key, and inspect the vehicle's computer for any issues.

5. Can I repair the OBDII code P1649 on my 2015 GMC Sierra myself?

- Depending on the cause, you may be able to resolve the issue yourself by programming a new key, reprogramming the immobilizer system, or resetting the vehicle's computer. However, if unsure, it's best to consult a professional mechanic.

6. Is it safe to continue driving my 2015 GMC Sierra with OBDII code P1649?

- It is not recommended to drive the vehicle with this code as it can lead to potential starting issues or the vehicle not starting at all. It's best to address the problem promptly.

7. How much does it cost to fix OBDII code P1649 on a 2015 GMC Sierra?

- The cost of fixing this code can vary depending on the cause of the issue. It may range from a simple key reprogramming cost to a more complex immobilizer system repair cost.

8. Can a dealership help me with OBDII code P1649 on my 2015 GMC Sierra?

- Yes, a dealership or a qualified automotive locksmith specializing in immobilizer systems can assist in diagnosing and resolving the issue related to code P1649.

9. Will resetting the battery clear OBDII code P1649 on a 2015 GMC Sierra?

- Resetting the battery may temporarily clear the code, but if the underlying issue is not addressed, the code is likely to return. It is recommended to diagnose and fix the root cause.

10. How can I prevent OBDII code P1649 from appearing on my 2015 GMC Sierra in the future?

- To prevent code P1649, ensure your transponder key is in good condition, program new keys properly, and regularly maintain your vehicle's immobilizer system to avoid any future issues.