You don't say what model or year you have, but the connection between the handle and the latch is purely mechanical. The computer and car alarms have nothing to do with it.
Could it be that the door is frozen shut? If the weatherstrip is wet and the temperature drops, the whole seal around the door can freeze. If that happens, pulling the inside or outside handle will unlatch the door but if the door is frozen, it won't move, making it seem that the latch is not unlatching.
Pouring a bucket of very warm tap water around the edge of the door is usually enough to thaw out the weatherstrip allowing you to open the door. If you choose that route, have a towel handy to dry off the weatherstrip and door jamb so as not to get a re-run of the problem as soon as it cools down. A light spray of silicone spray around the weatherstrip can be helpful to prevent recurrence. DON'T use a petroleum based lubricant like WD-40 or you'll deteriorate the weatherstrip.
If you are convinced that freezing is not the source of the problem, you'll need to get in there and check the mechanism. It may just need some lubrication.