In-Car-Entertainment Hacks

Radio removal
Ever wanted to yank that stock puppy out and put something better in? Here is how..
Improving your chassis ground (Big 3)
The stock focus battery grounds, engine grounds, and alternator cable are sufficient for a stock car, but when you start putting more draw on the system, its weaknesses show. Upgrading your chassis ground will help your car's electrical system perform it's best. Pretty much anything in your Focus that relies on electricity can benefit from it. That includes the car's own PCM and any ICE/Audio equipment you might have installed.
Make your own MP3 Harness
The Blaupunkt MP3 player came in quite a few Foci in 2002-2004. It requires a different harness, which can be made from readily available parts for under $40.
Reset a power cycling Blaupunkt MP3 head unit
Sometimes, when adding a radio preset channel, the Ford Blaupunkt MP3 stereo CD/mp3 player will lock up, then start turning itself on and off. It's possible to fix it with a factory reset, but it's tricky. Here's how.