Red-Candy-Metallic
Member
In the hope of helping others, I will share my own experience with spare keys, both good and bad.
First the bad. When I bought my 2014 GT in June of 2023, it only had one key. I bought a key blank and had it cut, but I didn't realize that you had to have two working keys to program it yourself. I made the mistake, from a cost perspective, of going to a Ford dealer to buy a second key and have it programmed. I was handed a bill for a "jaw dropping" $420 (the cost of the key blank plus the programming). Once I had two working keys, I did manage to program the blank that I had bought, so I shouldn't be at the mercy of a dealer again. This also made me realize why a second key is a negotiating condition when buying a used car.
Now the good. Having experienced my error in judgement with my 2014 GT, I realized that it would be a good idea to have a third key for my 2012 GT. I have owned that car since new and have both original keys. I bought a nice replacement blank from Amazon for less than $20 and had it cut at Ace Hardware for around $5. I followed the programming instructions from the owner's manual and the key started the car. I did have to program the buttons separately, but that was simple enough. The programming process took me around 15 minutes, but it could certainly be completed faster. So, for under $30 you can have a third key that will allow you to repeat this process if you lose one of you other two keys. I believe the manual states that you can have up to eight keys programmed, but I would imagine that to be a rare use case.
This is the key blank I used: Replacement Key
These are the instructions for getting the replacement key to start the car, per the owner's manual:
1. Insert the first previously programmed coded key into the ignition.
2. Turn the ignition from the 1 (off) position to the 3 (on) position. Keep the ignition in the 3 (on) position for at least three seconds, but no more than 10 seconds.
3. Turn the ignition to the 1 (off) position and remove the first coded key from the ignition.
4. After three seconds but within 10 seconds of turning the ignition to the 1 (off) position, insert the second previously coded key into the ignition.
5. Turn the ignition from the 1 (off) position to the 3 (on) position. Keep the ignition in the 3 (on) position for at least three seconds, but no more than 10 seconds. Locks and Security 114 2012 05+ Mustang (197) Owners Guide, 3rd Printing USA (fus)
6. Turn the ignition to the 1 (off) position and remove the second previously programmed coded key from the ignition.
7. After three seconds but within 20 seconds of turning the ignition to the 1 (off) position and removing the previously programmed coded key, insert the new unprogrammed key (new key/valet key) into the ignition.
8. Turn the ignition from the 1 (off) position to the 3 (on) position. Keep the ignition in the 3 (on) position for at least six seconds.
9. Remove the newly programmed coded key from the ignition. If the key has been successfully programmed it will start the vehicle's engine and will operate the remote entry system (if the new key is an integrated keyhead transmitter). The theft indicator light will illuminate for three seconds and then go out to indicate successful programming.
Note: Although the key would start the car after this procedure, I still had to follow a separate procedure for programming the 4 buttons.
This is a video on programming the 4 buttons on the key: Button Programming
First the bad. When I bought my 2014 GT in June of 2023, it only had one key. I bought a key blank and had it cut, but I didn't realize that you had to have two working keys to program it yourself. I made the mistake, from a cost perspective, of going to a Ford dealer to buy a second key and have it programmed. I was handed a bill for a "jaw dropping" $420 (the cost of the key blank plus the programming). Once I had two working keys, I did manage to program the blank that I had bought, so I shouldn't be at the mercy of a dealer again. This also made me realize why a second key is a negotiating condition when buying a used car.
Now the good. Having experienced my error in judgement with my 2014 GT, I realized that it would be a good idea to have a third key for my 2012 GT. I have owned that car since new and have both original keys. I bought a nice replacement blank from Amazon for less than $20 and had it cut at Ace Hardware for around $5. I followed the programming instructions from the owner's manual and the key started the car. I did have to program the buttons separately, but that was simple enough. The programming process took me around 15 minutes, but it could certainly be completed faster. So, for under $30 you can have a third key that will allow you to repeat this process if you lose one of you other two keys. I believe the manual states that you can have up to eight keys programmed, but I would imagine that to be a rare use case.
This is the key blank I used: Replacement Key
These are the instructions for getting the replacement key to start the car, per the owner's manual:
1. Insert the first previously programmed coded key into the ignition.
2. Turn the ignition from the 1 (off) position to the 3 (on) position. Keep the ignition in the 3 (on) position for at least three seconds, but no more than 10 seconds.
3. Turn the ignition to the 1 (off) position and remove the first coded key from the ignition.
4. After three seconds but within 10 seconds of turning the ignition to the 1 (off) position, insert the second previously coded key into the ignition.
5. Turn the ignition from the 1 (off) position to the 3 (on) position. Keep the ignition in the 3 (on) position for at least three seconds, but no more than 10 seconds. Locks and Security 114 2012 05+ Mustang (197) Owners Guide, 3rd Printing USA (fus)
6. Turn the ignition to the 1 (off) position and remove the second previously programmed coded key from the ignition.
7. After three seconds but within 20 seconds of turning the ignition to the 1 (off) position and removing the previously programmed coded key, insert the new unprogrammed key (new key/valet key) into the ignition.
8. Turn the ignition from the 1 (off) position to the 3 (on) position. Keep the ignition in the 3 (on) position for at least six seconds.
9. Remove the newly programmed coded key from the ignition. If the key has been successfully programmed it will start the vehicle's engine and will operate the remote entry system (if the new key is an integrated keyhead transmitter). The theft indicator light will illuminate for three seconds and then go out to indicate successful programming.
Note: Although the key would start the car after this procedure, I still had to follow a separate procedure for programming the 4 buttons.
This is a video on programming the 4 buttons on the key: Button Programming