Black plate (21,1)Cadillac DTS Owner Manual - 2011The security light will come on if there is a problem witharming or disarming the theft-deterrent system.When the PASS-Key ® III+ system senses that someoneis using the wrong key, it prevents the vehicle fromstarting. Anyone using a trial-and-error method to startthe vehicle will be discouraged because of the highnumber of electrical key codes.If the engine does not start and the security light comeson when trying to start the vehicle, there may be aproblem with your theft-deterrent system. Turn theignition off and try again.If the engine still does not start, and the key appears tobe undamaged, try another ignition key. At this time,you may also want to check the fuse, see Fuses andCircuit Breakers on page 6‑104. If the engine still doesnot start with the other key, your vehicle needs service.If your vehicle does start, the first key may be faulty.See your dealer who can service the PASS-Key ® III+ tohave a new key made. In an emergency, contactRoadside Assistance.It is possible for the PASS-Key ® III+ decoder to “learn”the transponder value of a new or replacement key. Upto 10 keys may be programmed for the vehicle. Thefollowing procedure is for programming additional keysonly. If all the currently programmed keys are lost or donot operate, you must see your dealer or a locksmithwho can service PASS-Key ® III+ to have keys madeand programmed to the system.See your dealer or a locksmith who can servicePASS-Key ® III+ to get a new key blank that is cutexactly as the ignition key that operates the system.To program the new key:1. Verify that the new key has a 1 stamped on it.2. Insert the original, already programmed, key in theignition and start the engine. If the engine will notstart, see your dealer for service.3. After the engine has started, turn the key toLOCK/OFF, and remove the key.4. Insert the new key to be programmed and turn it tothe ON/RUN position within five seconds of turningthe original key to LOCK/OFF.The security light will turn off once the key hasbeen programmed.5. Repeat Steps 1 through 4 if additional keys are tobe programmed.If you lose or damage your PASS-Key ® III+ key,see your dealer or a locksmith who can servicePASS-Key ® III+ to have a new key made.Do not leave the key or device that disarms ordeactivates the theft deterrent system in the vehicle.3-21