Where is the theft control module on a 01 buick pa ultra 3.8sc? pn10355946 Anything to know before replacing it? relearn key on 15 off 10 on 15 right? How about changing the steering sensor?

You have Passkey III - the actual module is part of the ignition switch and it sends class II data messages to the PCM.

A 2000 is also Passkey III but would need to be reprogrammed with a scan tool

If replacing a theft deterrent control module, the module will learn keys immediately. The existing PCM however, must learn the new fuel continue password when the theft deterrent control module is replaced