AutoCodes – Buick – P1649 Buick

P1649 Buick 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 Buick 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 1,014

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 Buick 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 Buick - Immobilizer Security Code Not Programmed - AutoCodes.com — P1649 Buick Code - Immobilizer Security Code Not Programmed

What does this mean?

What are the Possible Causes of the DTC P1649 Buick?

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 Buick?

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 Buick 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 Buick code?

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Need Help with the Code?

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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 Buick Code

1. What are the common symptoms of OBDII code P1649 (Buick) related to the immobilizer security code not being programmed?

- The common symptoms include the engine not starting, the vehicle not responding to the key fob, and the security light flashing on the dashboard.

2. What are the possible causes of OBDII code P1649 (Buick) indicating that the immobilizer security code is not programmed?

- The possible causes include a faulty key fob, a damaged immobilizer system, or a problem with the vehicle's computer system.

3. How can I diagnose OBDII code P1649 (Buick) if I suspect the immobilizer security code is not programmed?

- You can diagnose the issue by checking the key fob battery, ensuring the key fob is properly synced with the vehicle, and using a diagnostic scanner to read the trouble code.

4. Can I reset OBDII code P1649 (Buick) related to the immobilizer security code not being programmed?

- Yes, you can try resetting the code by disconnecting the vehicle's battery for a few minutes and then reconnecting it to see if the issue resolves.

5. What are some repair tips for addressing OBDII code P1649 (Buick) indicating an issue with the immobilizer security code?

- Repair tips include reprogramming the key fob, checking the immobilizer system for any faults, and consulting a professional mechanic for further diagnosis and repair.

6. Is it safe to continue driving my Buick with OBDII code P1649 indicating an immobilizer security code issue?

- It is not recommended to drive the vehicle with this issue as it may result in starting problems or potential security risks. It's best to address the problem promptly.

7. How much does it typically cost to fix OBDII code P1649 (Buick) related to the immobilizer security code not being programmed?

- The cost of fixing this issue can vary depending on the exact cause, but it may involve reprogramming the key fob, repairing the immobilizer system, or replacing components, which could range from $100 to $500 or more.

8. Can I program the immobilizer security code myself to resolve OBDII code P1649 (Buick)?

- Programming the immobilizer security code typically requires specialized equipment and knowledge, so it is recommended to have this done by a professional mechanic or dealership.

9. Will OBDII code P1649 (Buick) cause any long-term damage to my vehicle if left unresolved?

- Leaving this issue unresolved may lead to starting problems and potential security risks, but it is unlikely to cause long-term damage to the vehicle.

10. Are there any preventive measures I can take to avoid encountering OBDII code P1649 (Buick) related to the immobilizer security code?

- To prevent this issue, ensure your key fob is in good condition, avoid dropping or damaging it, and regularly check the functionality of the immobilizer system to address any issues promptly.