antitheft device, 99 grand cherokee

I have a 99 jeep grand cherokee. It has an antitheft device where I have to put a small round metal pin key into a metal hole under my dash so I can enable starting the car. If I don't get the pin key exactly into the hole the car won't start. It has become such a nuisance that I would like to disable this device. Can someone please tell me what this device is called and how to disable it? I think it has 5 wires running into the back of this small black device. I have tried doing research on it and I can't find any info on it. Thankssteve

It's an imobiliser, assuming you are in UK, forget te wires you mentioned, the main unit is probably up behind the instrument panel. It wil have 2 grounds, 3 ignition  2 starter and 1 power supply all coloured black. The ign or fuel line and starter need to be rejoined and the box thrown away. I remove  three or four a month. Totally irrelevant on modern vehicles. Just be aware you might have negated your insurance if you are in UK or parts of Canada.