Losing or damaging your car keys can be a stressful experience, especially with modern vehicles like the 2009 Mazda CX-9 that utilize sophisticated key fob systems. If you’re facing the need for a 2009 Mazda Cx-9 Key Fob Replacement, you might be daunted by dealership costs and complex programming procedures. This guide provides a detailed, experience-based approach to replacing your Mazda CX-9 key fobs yourself, potentially saving you a significant amount of money. While this process is not for beginners and involves some technical steps, it can be achieved with the right tools and information.
My Journey with Mazda CX-9 Key Fob Troubles
Like many Mazda CX-9 owners, I encountered the frustrating situation of dealing with lost and broken key fobs. My primary key fob and blade vanished, leaving me with a damaged spare and a single functional blade. The spare fob, even after a battery replacement, remained unresponsive – the indicator light stubbornly refusing to blink.
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Image of the advanced keyless entry or creditcard style FOB for Mazda CX-9
Upon disassembling the broken fob (a task that proved to be quite challenging due to the glued casing), I discovered a broken battery connector on the circuit board (PCB). Attempting a repair, I ordered an empty shell case online, hoping a simple PCB swap would solve the issue.
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Image of the empty shell case for Mazda key fob
While the PCB fit into the new shell, my soldering attempts to fix the battery connector were unsuccessful due to the broken piece’s shortness. As a further attempt, I experimented with an external battery holder glued to the case’s back. Unfortunately, this too failed, as I later realized that one of the copper antennas on the PCB had broken during the transfer, resulting in unreliable lock/unlock functionality.
Finding Replacement Key Fobs and Blades
Faced with these setbacks, I knew I needed to find replacement key fobs. The dealership quoted a hefty $350 per fob, excluding programming, prompting me to explore alternative solutions. Online, I discovered www.abkeys.com, which offered new key fobs for a more reasonable price of $125 each (blade not included). Ordering two, I was pleased to receive genuine Mazda fobs in original packaging.
With the empty shell case I had previously ordered, I also received an uncut key blade. However, my attempts to get the blade cut at local stores like Home Depot and Autozone were unsuccessful. A locksmith quoted a steep $120 for the service but suggested the Mazda dealer, who offered key cutting for just $20. At the dealership, after presenting my car title and ID, they readily cut the key blade.
The Transponder Chip Realization
Driving home, it dawned on me that the newly cut key blade likely lacked a transponder chip. A quick online search confirmed this suspicion. I then purchased a blade with a 4D-63 transponder for $20 online from https://carkeysexpress.com/store/ke…09/1001167-mazda-transponder-key-blade-insert. Returning to the Mazda dealer, I repeated the key cutting process with the transponder blade.
Important Note: Mazda dealers can cut a new key blade based on your VIN, even without an original key present.
Programming Key Fobs and Transponder with FORscan and Mazda IDS
Acquiring the replacement fobs and transponder blades is only part of the process. To make them functional with your 2009 Mazda CX-9, programming is essential. This requires either FORscan or Mazda IDS software to pair both the transponder chip in the blade and the new key fobs with your vehicle. Resources like FORscan tips can be helpful.
Having already invested in a VCM USB module and Mazda IDS software, I proceeded with the programming:
- Connect to Mazda IDS: Launch Mazda IDS, connect to your vehicle, and verify the VIN.
- Access PATS Menu: Navigate to the “programming” section and enter the “PATS” (Passive Anti-Theft System) menu. Ensure all doors are closed throughout this process to ensure proper lock/unlock functionality later.
- Obtain Outcode (If Required): For my 2009 CX-9, an outcode was necessary for security access. I used www.autokeyprog.com to obtain this.
- Gain Security Access: Enter the outcode in Mazda IDS to gain security access for programming.
- Program Ignition Key: Select “Program additional ignition key,” follow the on-screen prompts to remove the working key and insert the new transponder blade. Confirm the programming.
- Program Remote Key Fob: Choose “Program additional remote key.” Place the new, unprogrammed fob on the passenger seat as instructed. The doors will lock and unlock. Press the “unlock” button on the new fob twice. The car should respond with another lock/unlock cycle, confirming successful fob programming.
- Repeat for Additional Fobs: Follow the same “Program additional remote key” procedure for any other new key fobs.
After these steps, I successfully programmed two new key fobs and paired two transponder blades, restoring full key functionality to my Mazda CX-9.
Important Considerations Before You Begin
Before embarking on this DIY key fob replacement journey, keep these crucial points in mind:
- Verify FCC ID: Check the FCC ID on your original remote key fob (located on the back, near the blade insert). Ensure the replacement fob matches this ID.
- Button Layout: Confirm the button layout of your original fob (3-button, 4-button, with or without auto liftgate/panic button) and order the correct replacement.
- Frequency (MHz): Verify the correct MHz for your market (US market frequencies differ from European ones). Reputable suppliers like ABKeys usually specify this in the product description.
- Part Number (Optional): You can contact a Mazda dealer with your VIN to obtain the original part number for your key fob. However, be aware that part numbers might cover multiple button variations, so FCC ID and button layout remain critical.
- Two Working Blades Minimum: Crucially, ensure you have at least TWO programmed transponder blades before starting any programming. If you only have one working blade and something goes wrong, the PATS module might lock you out, preventing the car from starting. Get a new transponder blade cut before attempting any programming if you only have one working key.
- Minimize Interference: While programming, keep your cell phone and other potential sources of radio interference outside the vehicle. While the impact is uncertain, it’s a good precautionary measure.
- Transponder Blade Cost: Be wary of extremely cheap key blades (e.g., $2). These likely lack a transponder chip and are useless for starting the car. Blades with transponders typically cost between $10 and $20.
- Transponder Verification Tip: If unsure if a blade has a transponder, try inserting it into the door lock. A blade without a transponder will fit in the lock cylinder but will not allow you to turn the lock. A transponder-equipped blade will allow you to turn the lock (though it won’t start the car until programmed).
Conclusion
Replacing your 2009 Mazda CX-9 key fobs yourself is a complex but achievable task that can save you a significant amount compared to dealership prices. By carefully following these steps, ensuring you have the correct parts and software, and heeding the important considerations, you can successfully regain full key functionality. While this guide offers a comprehensive overview, always exercise caution and consult professional resources if you encounter difficulties or are unsure about any step in the process.
