My parking brake light came on last night as I was leaving a parking garage. I stopped, opened the door, and watched and felt the pedal as I pulled the release. The pedal raised up about 1/4" or less so it had been bumped: So I bumped this thread.

 

I pay close attention not to bump it and the break engages every 2-3 days anyway. I think the shock which pushes the pedal down needs to be replaced to add more pressure against accidental bumps or vibrations. Sewell has replacement shock for $60 with CL discount.

http://lexus.sewellparts.com/oem-cat...S430-2004.html