How To Reprogram Car Keys That Are Already Programmed


Fast and Reliable Electrical Service

Whatsapp Image 2023 11 13 At 11.24.26 (1)

Reprogramming car keys that are already programmed can seem like a daunting task, but with the right information and tools, it’s a manageable process. Whether you need to reprogram your keys due to a lost key, a new key fob, or after replacing your car’s battery, understanding the steps involved is crucial. In this guide, we’ll walk you through how to reprogram car keys, provide tips for ensuring success, and discuss the benefits of professional assistance from trusted locksmiths like Lulu’s Mobile in Irving, TX & the DFW area.

Whatsapp Image 2023 11 22 At 15.33.02 (1)

Understanding Car Key Reprogramming

Why Reprogram Car Keys?

Reprogramming car keys may be necessary for various reasons, including:

  • Lost Keys: Ensuring old keys cannot access your vehicle.
  • New Key Fob: Programming a new key fob to work with your car.
  • Battery Replacement: Reprogramming keys after a battery change in your car or key fob.

Types of Car Keys

Different types of car keys may require different reprogramming methods:

  • Transponder Keys: Contain a chip that communicates with the car’s ignition.
  • Key Fobs: Used for keyless entry and ignition systems.
  • Smart Keys: Advanced key fobs that offer additional features like remote start.

Steps to Reprogram Car Keys

Gather Necessary Information and Tools

Before starting the reprogramming process, ensure you have the following:

  • Owner’s Manual: Specific instructions for your vehicle model.
  • Existing and New Keys: All keys you want to reprogram.
  • Programming Device: Some cars require a special device for key programming.

Step-by-Step Reprogramming Guide

Step 1: Enter Programming Mode

  1. Insert Key: Insert the key into the ignition and turn it to the “On” position without starting the engine.
  2. Cycle Key: Turn the key to the “Off” position and then back to “On” several times. The exact number of cycles varies by vehicle; consult your owner’s manual.
  3. Watch for Indicators: Look for the car’s security light to flash or stay solid, indicating that the vehicle is in programming mode.

Step 2: Program the New Key

  1. Insert New Key: Insert the new key into the ignition and turn it to the “On” position.
  2. Wait: Leave the key in the “On” position for about 10 minutes or until the security light turns off. This allows the car to recognize the new key.
  3. Cycle Off and On: Turn the key to the “Off” position and then back to “On” to complete the programming process.

Step 3: Test All Keys

  1. Test New Key: Attempt to start the car with the newly programmed key to ensure it works correctly.
  2. Test Existing Keys: Verify that all existing keys still work with the vehicle to ensure no programming errors occurred.

Tips for Successful Reprogramming

  • Consult the Manual: Always refer to your car’s owner’s manual for specific instructions and key cycling sequences.
  • Have All Keys: Ensure you have all keys present during programming to prevent any from becoming deprogrammed.
  • Battery Health: Make sure your car and key fob batteries are fully charged before starting the process.

Professional Assistance

Benefits of Professional Reprogramming

  • Expertise: Professional locksmiths have the knowledge and tools to reprogram keys accurately.
  • Convenience: Mobile locksmiths can come to your location, saving you time and hassle.
  • Security: Professionals ensure that all keys are properly programmed and deprogrammed, enhancing vehicle security.

Choosing a Locksmith

When selecting a locksmith for key reprogramming, consider:

  • Experience: Look for locksmiths with experience in car key programming.
  • Reputation: Check reviews and ratings to find a reliable service provider.
  • Services Offered: Ensure the locksmith can handle your specific key type and vehicle model.

For trusted and professional assistance in Irving, TX & the DFW area, contact Lulu’s Mobile.


Can I reprogram my car key myself?

Yes, many car keys can be reprogrammed at home using the vehicle’s ignition and following the specific steps in the owner’s manual. However, some keys may require professional equipment and expertise.

What should I do if my car key programming fails?

If reprogramming fails, double-check the steps in your owner’s manual. Ensure all keys are present and that the batteries are charged. If issues persist, contact a professional locksmith.

How much does it cost to reprogram a car key?

The cost varies depending on the vehicle make and model, and whether you go to a dealership or a locksmith. Locksmiths often offer competitive pricing compared to dealerships.

Can a locksmith program all types of car keys?

Many professional locksmiths can program a wide range of car keys, including transponder keys, key fobs, and smart keys. However, it’s best to confirm with the locksmith beforehand.

How long does car key reprogramming take?

The reprogramming process typically takes 10-30 minutes, depending on the vehicle and key type. Complex systems or multiple keys may take longer.

What information do I need to provide to reprogram my car key?

You’ll need your Vehicle Identification Number (VIN), proof of ownership, and all keys you wish to reprogram.

Maximizing Your Vehicle’s Security

Deprogram Lost or Stolen Keys

If your keys are lost or stolen, deprogramming them is essential to prevent unauthorized access. A professional locksmith can help you deprogram the old keys and program new ones.

Use Advanced Security Features

Consider installing additional security features like:

  • Steering Wheel Locks: Provide a physical barrier to deter thieves.
  • Alarm Systems: Alert you to unauthorized access attempts.
  • GPS Trackers: Help locate your vehicle if it’s stolen.

Keep Keys Safe

  • At Home: Store keys in a secure location, away from doors and windows.
  • On the Go: Use key pouches with RFID protection to block signal interception.

Understanding the Importance of Professional Services

Expertise and Tools

Professional locksmiths have the necessary tools and expertise to handle key reprogramming efficiently and securely. They can address issues that might arise during the process.

Warranty and Support

Professional services often come with warranties and support, providing peace of mind if something goes wrong with your new key.


Professional locksmiths, especially mobile ones, offer the convenience of coming to your location, saving you time and effort.

Preventing Future Car Key Issues

Regular Maintenance

  • Battery Check: Regularly check and replace the battery in your key fob.
  • Clean Contacts: Keep the key and ignition contacts clean to ensure proper communication.
  • Software Updates: Ensure your car’s software is up-to-date to avoid compatibility issues.

Storing Spare Keys

  • Secure Location: Keep spare keys in a safe place to prevent loss or theft.
  • Avoid Outdoors: Don’t hide spare keys outside your vehicle, as this can be easily discovered by thieves.

Education and Awareness

  • Know Your Key: Understand the type of key your car uses (transponder, key fob, smart key, etc.).
  • Stay Informed: Keep up with the latest security measures and advancements in key technology.


Reprogramming car keys that are already programmed can be a straightforward process if you follow the correct steps and use the right tools. Whether you attempt the reprogramming yourself or seek professional assistance, ensure you understand your vehicle’s specific requirements and have all necessary information at hand.

By taking proactive steps to maximize your vehicle’s security, such as deprogramming lost or stolen keys and utilizing additional security measures, you can protect your vehicle and enjoy peace of mind.

For expert assistance and reliable service in Irving, TX & the DFW area, contact Lulu’s Mobile, your trusted locksmith. With their experience and dedication to customer satisfaction, you can rest assured that you’re in good hands.

Share This :

Same Day Emergency Service

Fast, reliable same-day emergency locksmith services ensuring immediate help for lockouts and security issues in Irving, TX, and DFW.