OK. It took me a while to figure this one out on my 92, but here goes. There is a float in the master cylinder reservoir shaped like a donut. It's attached to the cap and there are wires coming out which plug into the wiring harness. The float senses the level of fluid in the reservoir. What happened to mine was that, over time, the float gets a little hole in it and starts to sink. It's only occasionally at first, but eventually it will begin to stay on all the time. This gives the false impression that the fluid level is low, and the light comes on, on the dash. On my 92 it also kicked off the cruise control, if it was engaged. I didn't price the replacement cap/float system. I figured it was pretty expensive and a part that could only be had directly from Toyota. My solution: I unplugged the wires. End of problem. Cruise still works. Have no idea if the rear anti=lock works, cuz i haven't had the opportunity to get on the brakes that hard on a slippery surface. Try unplugging the wires and see if the problem goes away.
Mike in AR
