Last night I replaced the rear brake pads on my 04 IS300. Now when (and only when) the car is in Park, I hear a click each time I press and release the brake pedal. The click is coming from underneath the gear shifter (center console). I've read that this is probably the shift lock mechanism and that it's normal, but my question is this: Why didn't I hear that sound before I did the brake job? What could I have done to make the click noise suddenly appear? Believe me, I am very attuned to little noises in my car that aren't "normal," and I've had this car for at least 3 years and I'm positive I would have noticed that click before if it was there. I swear I have never heard that click noise before.