2000 cadillac dts My key is stuck in the ignition and will not turn to the OFF position

Ignition cylinder could of been worn and key no longer matches tumblers.

Ignition Lock Cylinder Control Actuator
The vehicle it is equipped with a floor mounted console gear shifter, and has a ignition lock cylinder control actuator system in the steering column as an added safety feature. The ignition lock cylinder control actuator systems purpose is to prevent the steering wheel from being locked when the transmission is in gear and the vehicle may still be moving. The ignition lock cylinder control actuator system consists of the BCM, the lock cylinder relay, and the ignition lock cylinder control actuator. The ignition lock cylinder control actuator contains a pin that is spring loaded out to mechanically prevent the ignition key cylinder from being turned to the lock position when vehicle speed is above 5 mph for 15 seconds and the transmission is not in the Park position. If vehicle power is lost, and/or the transmission is not in the Park position the operator will not be able to turn the ignition key to the lock position and will not be able to remove the ignition key from the column. For situations where the vehicle must be towed, the system can be overridden by pressing a release button that is reached through an access hole located on the under side of the steering column. First, remove the black plug covering the hole.

There isn't one. The 2000 DTS has a VATS security system. The car has to have the right key in the ignition for the system to turn on the fuel pump and the ignition system. Without those, the car no run.

If your battery is dead, the key will stay in. Try giving it a jump. Also check to see if the steering wheel is locked. If it is, try turning the steering wheel somewhat vigerously whilst trying to remove the key. Short of that, it's a common problem with those year GM vehicles. Their ignition switches suck badly

Pull steering wheel and replace iignition cylinder with new if won't start with every thing on then either starter and seilnoid if all in one if not then just seilnoid have some one help tap on starter and seilnoid see if starts that way if does then bad seilnoid other batt cables to starter jump it if that gets it then it's ignition switch good luck

It could be a bad ignition key assembly. The key assembly has a unit attached to it to read the Security code in the key and sometimes when these start to go bad they overheat bad. Go have it checked out by your mechanic.

Make sure your steering wheel isn't locked. Sometimes a key won't turn until you jiggle the wheel while trying to turn the key.

that is strange that the key will not release -- there is nothing electrical about the key being held in place. I would recommend trying to move the steering wheel back and forth as you try and turn the key/ignition back and forth and then back to off and try and get the key out then. if this does not do it then it sounds like something has gone wrong in the ignition switch itself and I would recommend jump starting the car and driving it down to your local automotive locksmith and see if they can get the key to release. the ignition might need to be re-pined and a locksmith can do this for you and get your key working good again.
hope it all works out,

c...

your switch is probably bad.. replace the ignition key and cylinder lock.

you can reset the system by turning key to on position for 5-10 mins and then try starting it but its probably a short or grounding prob try the engine to chassis ground