^ really? it says it in the schematic. behind the right kick panel. as far as what it does, it shuts off fuel if impact is detected. think of it as an accelerometer. it turns off fuel so if you are involved in a crash the fuel pump stops which also turns off the motor and prevents any opens in the fuel line to pump out fuel.
I don't have a picture as to what it looks like. I would go right to the fuel pump first (one of the easiest things to check) and make sure the pump works. and then move forward.
2001 ZX3 2.0L Zetec-
Hatch Nation #42
Going through Rebuild See "The TICK Build Thread" for details (http://www.focusfanatics.com/forum/showthread.php?t=289168&referrerid=62897)