Hey,

I had the same thing happen, and it was just a bad ground. In front of the battery, you'll find the ground cluster, where the main negative cable from the battery attaches to the body. There is also a row of male connectors with smaller wires attached to them. Check it out and if it's covered in gunk, disconnect it all and give it a thorough scrubbing (wire brush and some WD40 would do the trick). You may want to remove the battery for better access. The smaller wires don't reconnect in any particular order, so you can go to town on it. Give it a shot and let us know what happens.

Hope it helps. -Jonathan

PS: If it doesn't work, and you're worried about security, remove the fuse for the central locking system. You'll have to use the key and some of your dome lights won't come on, but it beats a stolen car.