Dash brake light turns on when braking

[superbox]

Hi!

My sedan has been running pretty well for the past six months with routine maintenance. Now the dashboard BRAKE light turns on when braking. There is no change in the braking power, it's pretty solid. My first thought, the parking brake wire is to blame and should be adjusted. Do you have a suggestion?

I just installed a new radiator to replace the rusting leaky old one. Hope I can keep this car running with your help and a little elbow grease! BTW, 115 for a new radiator at Kragen in Northern California, and the Automatic Transmission Fluid lines stock are not long enough to meet up with the new radiator.

Thanks, superbox

[earlyrizr]

usually an indication of low brake fluid in the master cyl. reservoir, can be because of worn brakes, or not likely but could be a leak in the brake system.

[dvc]

see if there arent any vacuum leaks. when i press brake pedal hard, fast and several times my (!) light comes on, after ~5sec it`s gone.

[Ghostyman]

As stated above, the most likely culprit is simply low brake fluid.

Where in the bay area are you?

[RobMilkshakes]

Definitely check the fluid. Mine started doing that when the fluid started getting close to the low line.

[toyotaspeed90]

Do not add fluid unless you can find a leak.

The brake system is designed so that it has a specific given space for fluid for a reason. As the brakes wear, the caliper pistons (and/or wheel cylinders) do not retract (they retract just enough to keep low to no friction between the mating surface and the brake pad surface). As they retract, as you can imagine, the fluid in the reservoir lowers because that amount of fluid is occupied in the space provided with less retractions.

IF you have a leak, yes you will have the fluid level lowering faster than the brake wear -- that should be solved before you add fluid.

[SuperRA]

Originally Posted by toyotaspeed90

Do not add fluid unless you can find a leak.

The brake system is designed so that it has a specific given space for fluid for a reason. As the brakes wear, the caliper pistons (and/or wheel cylinders) do not retract (they retract just enough to keep low to no friction between the mating surface and the brake pad surface). As they retract, as you can imagine, the fluid in the reservoir lowers because that amount of fluid is occupied in the space provided with less retractions.

IF you have a leak, yes you will have the fluid level lowering faster than the brake wear -- that should be solved before you add fluid.

Or his brakes could be worn enough to lower the fluid and trip the switch but not yet completely worn out. I've had this happen everytime my pads were nearing the limit.

[toyotaspeed90]

Originally Posted by SuperRA

Or his brakes could be worn enough to lower the fluid and trip the switch but not yet completely worn out. I've had this happen everytime my pads were nearing the limit.

pads are cheap.....

the light should only come on when they are worn quite a bit -- to the point to where at the very least in reverse the squeelers are making noise......

replace the pads..... don't want to sacrifice your rotors because you were too cheap to replace the pads when they were low.... and oops, there's some grinding.

Go to CSK or Napa and pick up a set of standard Ceramic pads -- better than oe for braking and have almost as good of wear rate as a Semi-metallic... they're in the $35 range or so.

[retiredat44]

Carquest Ceramic brake pads about $50.00

[superbox]

Update: It was low brake fluid due to fluid being pushed down into the system as the brake pads wore down. The owners manual noted this was what the problem was, and it was right! The little owners manual hasn't let me down yet. Thanks for the input on this one! Brake system works as before, but instead of the fluid being just below the low line, it's not just below the high line.