The 2003 Cadillac Deville Touring Sedan (DTS) is a full-size luxury car manufactured by General Motors. The DTS features a standard ignition key that is used to power and start the car. The transmission needs to be in "Park" in order to turn the ignition key. A shift lever that that is between gears or positions causes the key to become stuck in the key cylinder. An Engine Control Module (ECM) may also be going bad if the key won't turn. The ECM transmits data to the key cylinder allowing the key to be removed. Manually turn and remove a key with a faulty ECM.
Look at the gear shift indicator in the center console. The park indicator should light up orange to notify you that the car is in park. If the indicator does not light up, the ECM may not be transmitting data that the other modules need in order to release the key.
Insert a pen into the access hole located under the steering column near the lock cylinder.
Push the small plunger inside the access hole up. This releases the key cylinder.
Turn the key counterclockwise to the "Off" position.
Remove the key.
