If you need to repair or replace the radio in your 2002 Ford Focus, removing the factory-installed radio isn't a simple matter of popping it out. Ford takes a few steps to prevent stereo theft. You need a special set of tools to remove a Ford radio, which are used with the set of holes on the unit's right and left sides. These can be found at any store with auto electronics parts, but an audio speciality store is the best place to go. Also, a factory Ford radio has a special keycode antitheft system that is activated upon removal. You won't be able to work it again without the security code.
Open the bonnet and disconnect the cable from the Ford Focus's negative battery terminal.
Insert U-shaped removal tools into the holes that are in each side of the radio/stereo unit. This releases the unit's retaining clips. If you get special tools from an audio specialist, they can snap into the clips, and you can then pull the unit out.
Pull the U-shaped tools outward gently to remove the unit from the console. Pull it out as squarely as possible. If you shimmy the unit and try to pull it out at an angle, it can jam.
Disconnect all connectors to the radio from the back. This includes the power supply, the ground, the antenna and the speaker leads. There might also be a plastic support bracket to remove the unit from.
If you reinstall this or another radio unit with a keycode antitheft system, you must enter a security code for the unit to function again. The code is found in the Focus's audio operating guide. If the code is incorrectly entered three straight times, you must wait 30 minutes before trying again. After 10 straight failed attempts, the unit will completely shut down and not work without the manufacturer reprogramming it.