1990 Cadillac Seville Will not start, due to theft system

Broken wires up by the ignition lock cylinder. You can verify this with an ohmmeter. At the base of the steering column there is a large connector that is mated together with a bolt(7mm). With it disconnected, find the two small, white wires that emerge from an orange conduit. With your ohmmeter, measure the resistance across these two wires, in all ranges(accessory is not necessary). You should have the same resistance in all. You should not have O.L, or whatever your meter displays as open circuit. With that being said, if you know, or can figure out, your keys resistance value, you can place a resistor pack of the same value across the vehicle harness side of that connector as a bypass. It would be your option.

Your current resistor is the pellet in your key. If you have open circuit resistance when measured at the column side of the connector, you need an ignition cylinder and new keys. If you can determine the value of that pellet(don't touch the leads with your fingers as your body has resistance), then you can make a resistor pack(you will not find one resistor of the correct value, I am almost certain), and place it across the terminals on the harness side, this will bypass the cylinder.