No events led up to the failure. Wife drove car, brake warning comes up on dashboard, she pulled over. Wife called me on cell. I thought it w the parking brake. I told her to manipulate to clear the warning to no avail. Then I told her to open the hood to look at the brake cylinder. The brake cylinder had disconnected from its holder. A single pin holds it in place. This pin apparently broke causing the cylinder to fall over and release the brake fluid. The cylinder was layng over on its side dangling by two wires. My wife was about 80 miles from home visiting her parents. She thought she could drive home so it could be repaired by our dealer, dayton Toyota in dayton, NJ. I told her not to drive given that there was no brake fluid. If she had driven her stopping distances would have been a lot longer. We contacted aaa then a local Toyota dealer - star Toyota of bayside, NY. They arranged for a flatbed to bring the car to the dealership. The incident happened on a Sunday so it stayed at a aaa service station overnight. Star Toyota noted that they would work on it right away so my wife could drive home. They didn't work on it until Wednesday when I had to go get the car. Star replaced the cylinder sub assembly, bled the system and replaced the fluid. My concern is how many other 2004 Toyota Highlanders are out there with this type of defect. As noted there was no reason for teh failure of the pin holding the brake fluid cylinder. I think there should be a warning to dealers to check for this problem.

- West Windsor, NJ, USA