2001 keyless entry problem

i got my 2001 explorer sport used. it has keyless entry but i can open the car with it since i dont have the code. The manual says its on the owners card which i dont have, or the cars computer module. I cant quite figure out where the computer module is and it doesnt say it in the manual. Where would i find it?

The computor is located in the jack compartment on the drivers side rear cargo area. It is mounted on the wheel well, mine is white. It will take some doing to read the five digit number located on the tag adhered to the broad side of it, one AF member said us a mirror and a good flashlight. I just went to look at mine and managed to pull the trim back enough to read it. The mirror was no help to me, there was no room for it, the tag face towards the inside of the truck, but if the tag is on the opposite side, facing the outside, than a mirror is a must, the flashlight is important. If your jack is in another compartment, check that compartment for the computor. It almost always seems to be with the jack. Good luck!!