Are you an owner of an older Subaru Impreza, WRX, or STI, perhaps admiring the sleek, integrated key fobs of the later models? Since 2009, Subaru Legacy models boasted a stylish key with the remote seamlessly built-in, while many Impreza owners were left with the traditional separate key and teardrop remote. If you’ve been yearning for that modern, all-in-one key fob experience, you’re in luck. This guide is designed to walk you through upgrading to a 2011 Subaru Legacy Key Fob, bringing a touch of modern convenience to your trusty Subaru.
Understanding the Evolution of Subaru Key Fobs
For Subaru Impreza models from 2008-2010 (and Forester models from 2009-2010), the familiar teardrop remote was standard. Although these remotes might look similar to older Subaru remotes, they are uniquely designed and not compatible with other models. This initial incompatibility presented a challenge for those wanting to upgrade.
However, the good news is that with readily available parts, you can adapt your Impreza, WRX, or STI to use the more modern integrated key, or other remote options originally designed for the Legacy. Notably, if you own a 2011-2012 Impreza, the process is even simpler! You can directly use a 2011 Subaru Legacy key fob with minimal hassle. We’ll delve into the specifics for all models, but if you have a 2011-12 model, make sure to jump to the dedicated section further below to discover the streamlined approach for your vehicle.
The key to this upgrade lies in understanding the “keyless unit.” This small module, typically located in the rear of your Subaru, is responsible for receiving signals from your key fob and instructing the Body Integrated Unit (BIU) to manage door locking and unlocking. Crucially, this keyless entry function operates independently from other vehicle systems. This modular design is advantageous for us: by swapping out the keyless unit, we can effectively use remote fobs from different Subaru models.
Our primary focus will be on integrating a keyless unit from a 2005-2009 Subaru Legacy into an earlier Impreza to enable the use of Legacy remote keys. For those with 2011-2012 models, we’ll highlight the direct compatibility with 2011 Subaru Legacy key fobs, simplifying the process significantly.
Step-by-Step Procedure to Integrate a Legacy Key Fob
Let’s break down the process of upgrading to a Legacy integrated key fob. First, you’ll need to gather the necessary parts. This typically involves sourcing a Legacy keyless unit and compatible remote keys. While purchasing new parts is an option, exploring online marketplaces like eBay for used components can be a cost-effective approach.
Parts You’ll Need:
-
For 2008-2010 Impreza/WRX/STI:
- Legacy Keyless Unit (2005-2009): Part number 88035AG03A.
- Legacy Integrated Remote Key (2009): Part number 57497AG48A.
- New Key Blade/Shell: A replacement shell with an uncut key blade, readily available online.
-
For 2011-2012 Impreza/WRX/STI:
- 2011-2012 Legacy Key Fob: Part number 57497AJ10A (USA only) or 57497AJ00A (Canadian WRX and Legacy).
Sourcing Your Parts:
Ebay is often a great resource for finding these parts affordably. When searching for Legacy keys, familiarize yourself with the visual characteristics. The correct Legacy key for the 2005-2009 swap will resemble this:
Image of a 2009 Subaru Legacy integrated remote key, highlighting its all-in-one design.
Ensure the key you’re considering has the FCC ID CWTWBU766 marked on the back. It’s crucial that the key blade matches the visual example. Be cautious of sellers who only focus on FCC ID matching; visual confirmation is essential. If the key doesn’t precisely match the image, it’s best to return it and clarify with the seller.
You’ll notice that the 2009 Legacy key blade differs from the “laser cut” high-security key used in Imprezas. However, don’t worry about the blade itself at this stage, as you’ll be replacing it with a new blade compatible with your Impreza using the new key shell. Purchasing multiple keys and shells allows you to have spares. Keep in mind that after this modification, your original Impreza remotes will no longer function. Used Legacy keys can often be found for reasonable prices online.
For the keyless unit, eBay listings may be less descriptive. Search using the part number 88035AG03A and keywords like “chassis ECM” or “Theft/Locking; Keyless Entry (R. dash)” for a 2005-2009 Legacy. The part number is usually stamped directly on the unit for easy identification.
Image showing the part number label on a Subaru Legacy keyless unit, essential for identification when sourcing parts.
Assembling Your Integrated Key:
Once you have your parts, the next step is to assemble a functional key. This involves combining the remote functionality with a key blade cut for your car and a transponder chip programmed to start your vehicle.
Getting the key blade cut professionally is recommended. Contacting your Subaru dealer or a local locksmith is advisable. Dealer key cutting costs can vary, but it’s often the most reliable way to ensure a precise cut.
For the transponder chip, you have a couple of options. One straightforward method is to carefully remove the transponder chip from one of your existing Impreza keys and transplant it into the Legacy key. Since your original Impreza keys are already programmed to your car, this transferred chip will also be recognized. Alternatively, you can explore having a locksmith or dealer program new transponder chips to your used Legacy keys, although this may incur additional costs.
Transferring the Transponder Chip:
Let’s walk through extracting the transponder chip from your original key. On the back of your integrated key, you’ll find a small screw. Remove this screw to begin disassembling the key.
Image showing the back of the integrated key with the location of the retaining screw that needs to be removed for disassembly.
Carefully pry open the back cover starting from the key blade end. It should lift off with a slight slide. Inside, you’ll see the remote components and, importantly, the transponder chip.
Image showcasing the internal components of the integrated key, with a screwdriver tip pointing to the location of the transponder chip.
Use a small, stiff pin or similar tool to gently lever the transponder chip out of its housing.
Image displaying the disassembled key components, including the new key shell ready for reassembly.
If you’re using a used Legacy key, now is also the time to open the remote portion (the button module) to retrieve the 8-digit numeric code. This code is necessary for programming the remote to your car later.
Accessing the Remote Code:
The remote unit opens by releasing small latches around its perimeter. A small flathead screwdriver can be helpful for this.
Image highlighting the latches on the remote unit that need to be released to open it and access the programming code.
Once open, locate the sticker inside. The 8-digit numeric code you need is typically on the upper line of numbers. Record this code carefully. This is also a good opportunity to replace the battery in the remote, which is a CR1620 type.
Image of the inside of the remote unit showing the sticker with the 8-digit numeric code required for programming, and the battery compartment.
Preparing Your Original Key for Transponder Removal:
To access the transponder chip from your original Impreza key, you’ll need to open up its casing. Sacrificing a valet key or a spare key is usually the easiest approach. Using a utility knife or similar tool, carefully slice down both sides of the rubber covering of your original key. You’ll also need to cut around the keychain loop.
Image showing the process of slicing the rubber casing of an original Subaru key to access the transponder chip.
Once cut, the rubber covering will peel away, revealing the internal components.
Image displaying the original key with the rubber covering removed, exposing the plastic housing containing the transponder chip.
The white plastic part within the key houses the transponder chip. Snap this white plastic piece open to retrieve the chip inside. The transponder chip is the small black piece.
Image clearly showing the extracted transponder chip, a small black component crucial for starting the vehicle.
Final Key Assembly:
With the new key shell, your transferred transponder chip, and the Legacy remote, you’re ready to assemble your integrated key.
Image of all the components ready for final assembly into the new integrated key fob.
Have your new key blade cut to match your car’s ignition. As mentioned, dealer key cutting is often a reliable option.
Image of the fully assembled and cut integrated key, ready for use and programming.
At this stage, your new key should mechanically start your car thanks to the transferred transponder chip.
Swapping the Keyless Unit in Your Subaru
The final mechanical step is replacing your Impreza’s keyless unit with the Legacy unit. The location of the keyless unit varies slightly between hatchback and sedan models.
Hatchback Models:
For hatchback models, the keyless unit is located behind the upper trim panel on the driver’s side of the hatch area.
Image indicating the location of the upper trim panel in the hatchback where the keyless unit is situated.
Removing this trim panel involves detaching several screws and clips. Consulting your Subaru service manual for specific instructions is recommended. Alternatively, online resources or forums may provide detailed step-by-step guides. Behind this panel, you’ll find the keyless unit.
Image showing the keyless unit circled in red, located behind the trim panel in the hatchback.
The unit is secured with a single 10mm bolt. Remove this bolt to detach the unit.
Image highlighting the 10mm bolt that secures the keyless unit to the vehicle body.
Sedan Models:
For sedan owners, the keyless unit is located under the rear deck, behind the rear seats.
Image showing the location of the keyless unit in a Subaru sedan, situated under the rear deck behind the seats.
Unit Swap and Reassembly:
Once you’ve located and detached the Impreza keyless unit, carefully disconnect the plug from the bottom. You’ll notice that the form factor of the Impreza and Legacy units is similar, although the part numbers and mounting brackets differ.
Image comparing the Impreza and Legacy keyless units, highlighting their similar form factor but different part numbers and brackets.
The Legacy keyless unit will plug directly into the existing connector in your Impreza. However, you’ll need to swap the mounting brackets to properly secure the Legacy unit. Use a flat blade screwdriver to gently lever and detach the bracket from the Impreza unit and attach it to the Legacy unit.
Image demonstrating the process of swapping the mounting bracket from the Impreza keyless unit to the Legacy unit.
With the Impreza bracket on the Legacy unit, plug it in and bolt it back into its location.
Image showing the Legacy keyless unit installed in the vehicle after the bracket swap and bolting it back into place.
Finally, replace the trim panel in the hatchback or reassemble the sedan rear deck area. The physical installation is now complete!
Programming Your 2011 Subaru Legacy Key Fob
With the Legacy keyless unit installed and your integrated key assembled, the last step is to program the remote functions to your car. Remember that 8-digit code you recorded from inside the Legacy remote? You’ll need that now.
You have two options for programming:
- Dealership Programming: Take your Subaru to a dealership. Their diagnostic tools can easily program the remote by inputting the 8-digit code.
- DIY Programming: Subaru provides a DIY programming procedure. It can be a bit intricate initially, but with careful attention to the steps, you can program the remote yourself.
Refer to resources like cars101.com for detailed instructions on the Subaru remote programming procedure. You’ll need to repeat the programming process for each Legacy key fob you intend to use.
After successful programming, you should now have a fully functional integrated key that handles both keyless entry and ignition!
Bonus: Budget-Friendly Remote Options
Once you’ve completed this swap, you can expand your options for additional remotes. Any remote key fob designed for a 2005-2009 Subaru Legacy will now be compatible with your car. This opens up possibilities for finding even more affordable used Legacy fobs online as spares or replacements.
Simplified Approach for 2010 Legacy and 2011-2012 Subaru Models
2010 Subaru Legacy Option:
Alternatively to the 2005-2009 components, you can also use a 2010 Legacy keyless unit and 2010 Legacy keys. The 2010 Legacy key visually resembles the integrated key we’ve been creating, with a blade similar to Impreza keys.
Image of a 2010 Subaru Legacy integrated remote key, similar in appearance to the 2009 model but designed for the 2010 keyless system.
Ensure the key is advertised as a 2010 Legacy key and has the FCC ID CWTWBU766. Similar to the 2005-2009 swap, ensure visual confirmation matches the image and FCC ID. Use the 2010 Legacy keyless unit with 2010 Legacy keys as these systems are not cross-compatible with other years.
Part number references for 2010 Legacy components:
- Legacy Keyless Unit (2010): 88035AJ00A
- Legacy Integrated Remote Key (2010): 57497AJ00A (Also for 2010-2012 Canada Legacy).
2011-2012 Subaru Impreza, WRX, STI: The Easiest Upgrade!
If you own a 2011-2012 Subaru Impreza, WRX, or STI, upgrading to a 2011 Subaru Legacy key fob is incredibly straightforward. You can directly purchase a 2011-2012 Legacy key and it will be compatible with your existing system!
Look for a key that appears like this:
Image of a 2011-2012 Subaru Legacy integrated remote key, directly compatible with 2011-2012 Impreza models.
And crucially, confirm it has an FCC ID of CWTWB1U811 (USA Only). For Canadian models, 57497AJ00A with FCC ID CWTWBU766 (also used for Canadian 2011-12 WRX) will work. If the image and FCC ID don’t match these specifications, it’s not the correct 2011 Subaru Legacy key fob.
For 2011-2012 models, you can skip the keyless unit swap entirely! Simply follow the key assembly steps described earlier to create a functional key with your transferred transponder and the new 2011 Subaru Legacy key fob remote, and then program the remote to your car. Your original remotes will continue to function alongside your new integrated key.
Part number for the 2011-2012 Legacy key: 57497AJ10A (USA only).
By following these steps, you can significantly enhance the convenience and feel of your Subaru, bringing the modern functionality of a 2011 Subaru Legacy key fob to your older model. Enjoy the streamlined experience of an all-in-one key!
