How to Program New Ford Mustang Keys
- 1). Assemble your keys. Have at least two factory-programmed keys and all of the spare keys you wish to program close by before you start this procedure.
- 2). Insert one of the factory-coded keys into the ignition switch. Turn the key to the "On" position for between 1 and 10 seconds, then turn the key to the "Off" position and remove it from the ignition.
- 3). Insert the second factory-programmed key into the ignition switch within 10 seconds of removing the first one. Turn the key to the "On" position for between 1 and 10 seconds, then turn the key to the "Off" position and remove it from the ignition.
- 4). Insert the key to be programmed into the ignition switch within 20 seconds of removing the second factory-programmed key.
- 5). Turn the key to the "On" position for at least 1 second to program the key. Turn the key to start the engine.
- 6). Repeat the entire procedure to program additional keys.
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