I've been having the same issues with the abs light. I even cleaned all 4 abs sensors, but no luck. I spent $100 for the diagnostic thru dealership and read "front left speed sensor bad". I bought the part (yep $190) replaced but still have the abs light coming on occasionally!! I did not however jumped the terminals as what stated on the previous post. this has been an on-going problem for me for 3 years now. When abs light is not on when applied the brakes it works, but before the light comes back when applying the brakes, it would grind and sound a big spring coming un-done then the abs light would come back. So far, I only changed the front left speed sensor, I don't want to buy the rest of the 3 if it is not going to work. one thing that the dealsership had advised me is that to replace the entire abs unit ( $900 !! )
If someone could direct me to a site on how to jump the cables etc, it would be a good help. Thanks in advance.

ps. I've emailed/contacted toyota motor sales U.S.A. about this problem, here's the response:

"Thank you for contacting Toyota Motor Sales, U.S.A., Inc.
Your interest in Toyota producsts is appreciated.

We make every effort to manufacture a quality product by researching, testing, and constantly monitoring performance. Consumer opinion and perception also play an active role in our ongoing efforts to lead the automobile industry in quality, innovation, styling, and reliability.

Your feedback is appreciated; it is through communications such as yours that we become aware of our customers expectations and reactions. It also provides us with valuable insight when planning and developing future products and services to increase our customers' satisfaction.

Your comments regarding seeing these options on future versions of our products have been documented at our National Headquarters under file #200604111175 and are available for review by the appropriate departments.

Toyota Customer Experience "

but until today,no one has contacted me about this problem.