Hi, I have a question for all your men out there that may know how to answer this question, I feel so silly asking this sort of question because this makes me look so bad. However, I must ask it anayway, OK, I just bought a 2003 Murcury Sable LS, very nice car and seems like a perfect car for me, however, upon reading the handbook I noticed that the gas gage has a switch and is on/off switch which is located in the back of the car, now this may be an emergency switch or something; but tyring to take off the gas cap to fuel this car I realized another superise I could not remove it and with this type of car it comes with filer cap and for some reason I am not sure how it actually comes off. Like I said I feel really blonde right now, but I am not sure how to do this, it is not like a regular car I have driven before where I could just remove the cap and simply fill it up, so I am asking if someone could answer this for me. I need to put gas into this but I can not remove th cap.

Intriguing...
I am guessing you only recently got this car? Was it bought out of a fleet operation?
I'm not familiar with any switch that interferes with removing or replacing the gas cap.
There is a switch in the system that cuts off fuel in the event of a collision, etc, but that isn't the same as interferring with the cap itself.
Can you get a picture for us? That may help...

The switch in the trunk that you're talking about is the emergency cut-off switch... this is not your problem.

Is this the type of fuel cap that you're talking about?

Easy Fuel

Or is it maybe a locking cap?

Press the cap down and rotate counterclockwise (CCW). The Inertia Switch in the trunk is only there to cut the power off to the fuel pump, if the car is involved in an accident (to help prevent a fireball). It doesn't affect your problem.