The 2001 has an electric hatch lock and actuator. Your alarm/keyless entry remote will unlock the hatch by pressing the unlock button twice. If everything is working properly, you should then be able to use the little latch that's hidden in the "handle" area of the hatch to open it.

There are a couple of other ways to unlock the hatch and all but one require that the hatch lock actuator assembly work properly. If the electric lock and actuator are working properly, you can unlock the hatch with the door lock switch inside the door, you can also unlock it using your key in the drivers door. Turn the key and hold it for a second, the initial turn mechanically unlocks the driver's door, but by holding the key in the turned position for a second or two longer activates the car's electric door locks. Both doors and the hatch will unlock doing this.

The keyhole in the rear by the tail lights functions much in the same way. But, if I remember correctly, with one slight difference. The rear key/lock mechanism functions first as an electric switch to the entire lock system, then if turned harder/farther clockwise will also manually unlock/open the hatch.

I know all of this through experience only... my '99 Integra had a bad lock/latch actuator assembly thus keeping the hatch from operating properly as described above. I bought and installed a new actuator assembly and now my hatch lock/latch works. I was pretty sure it was an actuator problem because I could hear the electric lock working, but the hidden lever in the hatch handle never would open my hatch. This went on for about 2 years until I finally read a post by a former Acura mechanic saying they always throw an actuator at the problem I was describing. I bought the part for about $50 and it did the trick.

Sorry so long, probably more than you wanted to know.

JD