I can't lock and unlock my door using the key, only with the FOB. It's a 2002 Xterra. Is this the norm?

Odds are, they key may never have been used to open the doors (dont know if the X has been yours for long) . Lack of use could be the main reason, if by chance you do use the key lock on yours, and this is a NEW problem, then you would have to ask, Does it NOT work in all three key holes? or just in the drivers door??? ??? ?? ??

I have an 02 and the clip hole broke on my fob. I have been using the key only, for several years.
And there are only 2 keyholes.

Right. If you have the remote lock/unlock (i.e., you have the fob), then there's only a key hole on the driver's door and the hatch. The passenger side doesn't have one.

My thought is that it may have been re-keyed. If that were the case, the key would still work in the ignition, but not in the door. Either one getting re-keyed would do this with the end result being that you're missing one of the (now 2) needed keys.

-G

gee, never noticed that there isnt one on the pass side door !!! imagine that, guess that shows how much I've tried to use the key !!1 lol

2000X's had one on passenger side door.

I've been using the key only for years now. And you know what, I got a copy made for 6 bucks and it works just fine too. But I do miss my fob. Note to self, don't take that up the mountain again.

I just bought 2 new key fobs on ebay that come with easy-to-use programming instructions. I'll let you know how well they work. I also have re-keyed vehicle ignition keys. The original the owner left with her mechanic by mistake. I have two copies. They both work in the lock and the ignition. Sometimes it may not turn the first time so I may have to flip the key over of back it off a bit so the teeth hit the tumblers.

While we're on the subject, who designed that fob with the three in-line buttons. My old Ford had right/left lock/unlock with the panic button below - hard to accidentally push it. Nissan makes you feel in the dark for that middle unlock button so you don't push the panic alarm!!

I never had a problem with the fob buttons where they are, felt natural right away I can hit the right button even with gloves on.

Good experience with the after market new FOBs. Instructions were easy to follow and new one works great.

Got mine from http://www.keylessride.com/

But i think when you use the key fob to lock and unlock the door you have a problem in your door lock sensor after few months.And due to that the ignition system don't properly work and alarm set off.So you must use the key to lock and unlock the door.

Nope, the fobs work fine and there's no problems after a few years let alone a few months.