Security light

You're having a problem with the Passkey security system.

The most common failure in these is the sensor in the ignition lock that reads the key pellet. That would mean replacing the ignition lock with a sensor included.

That sensor can be bypassed although this is only one component of the system and my not be your problem. You would need a digital ohmmeter to measure the resistance of the pellet in the key. Now go to Radio Shack and buy a resister of the exact same value as the key pellet. Go to the base of the steering column and locate the two thin white wires that go up to the sensor. Cut the two wires and solder the resister between the two ends coming from the harness. This will permanently bypass the sensor but not the rest of the system.

You don't get to match key chips when you replace the lock cylinder. You have to replace the Passkey Module along with it so it will learn the new code.

No, you can't change the key. You have to change the module. A new module has no code programmed until the first time it's used. It can't be changed after that