This is stupid.

[JohnnyO]

I'm not aware that 1993's had a keyless entry. I think either a short or an aftermarket alarm.
I got a used Focus last year that had such a killer alarm in it that I took it to the dealer and spent $200 to have them pull it all out. You couldn't friggen' pump gas without the doors locking and the interlock kicking in.

 

[snake]

I keep the transmitter for the keyless entry on a seperate keychain from the ignition key- so when I'm driving, it is always in my pocket- get out screw up and lock the keys in, it is still in my pocket. Of course, both keychains are full, I just got a lot of keys...

But I agree, that aftermarket bastard is probably the culprit. Pull the fuse on it and see if it still does this.

 

[DeanMoriarty]

It's not the 93, it's an 01 Explorer... but I've done some research and it IS the aftermarket alarm causing it. It's possible to program it NOT to auto lock at all, if the place that installed it didn't activate a manual programming lockout. (I'm not holding my breath.) If they did then I'll have to take it somewhere that has a handheld alarm programmer... unless someone knows another way to bypass the lockout?
I'll get a few extra keys made in the meantime, lol.