I'm unsure of exactly what it is you are asking. The warning light itself is on the dashboard display as an orange circle with the picture of an engine in the center of it. It will light up when the computer senses is not "in specs" with the emission control system. It can mean several things; the two most common are - the gas tank cap is loose - the PCV valve needs replacement. I'd check your gas cap first (and also make sure that you have the right kind of cap), then replace the PCV valve, they are inexpensive. After you do that drive for a few dozen miles and the light should re-set. If it doesn't you will have to have a mechanic check further.
Check your brake fluid.
The 2003 Ford Focus has 16 valves.
The 2003 Ford Focus is a gas-powered vehicle.
The 2003 Ford Focus has a 5-speed manual.
The 2003 Ford Focus has an inline 4 engine.
http://www.focushacks.com/index.php?modid=88
The 2003 Ford Focus runs on regular unleaded.
The 2003 Ford Focus is 14 ft. 0.1 in. (168.1 in.) long.
The height of the 2003 Ford Focus is 4 ft. 8.3 in. (56.3 in.).
The 2003 Ford Focus has double overhead cam (DOHC).
The curb weight of the 2003 Ford Focus is 2598 lbs..
The 2003 Ford Focus's turning circle is 34.3 ft..