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Emergency Brake Light Problem

I have a 1999 Buick Lesabre. The emergency brake light/chime Keeps going off pretty much all the time now. I looked at the fuse box bother under the drivers side dash and under the hood, but couldnt find anything labeled emergency brake or related. Is there another fuse box besides those two?

Have you checked the level of your brake fluid yet? Often the emergency brake/light serves as a warning that the fluid is low in addition to the emergency brake being applied. (Please check this immediately before driving again!)

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In addition, it may be that the cable is sticking and not pulling the brake pedal all the way off. You have to reach under the car and pull on the cable while you are pulling up on the brake pedal to get the light to go off. Or the switch could be out of adjustment. Had the cable sticking problem on my Buick.

If it is the fluid…you may also want to check the pads because as the pad wear the caliper gets pushed in and this causes the reservoir to lower. So the light is caused by the fluid in reservoir lowering and the reservoir lowering is caused by the pads wearing down.

Low brake fluid level due to extreme pad wear does not trigger a emergency brale light on my Corolla. The level has to be extremely low to trigger it. Low brake level due to fluid loss(leak) or loss of hydraulic pressure will trigger it.Capturebrake cylinder

Notice how low the sensor is located on this diagram

On my Corolla I’ve had the dashboard brake warning light blink on when the brake fluid level got a little low , presumably due to pad and/or shoe wear. Topping the brake fluid off turned the light off. I checked both the pads and shoes, still within their wear limit.

Maybe they changed the design…mine is a 1999.

Yes, probably a design change, mine is older, early 90’s.

Thats not where the sensor is, that is where the wiring harness plugs in. The sensor is inside and higher up. When the fluid gets down to about where the parting seam is, or a little under it, the brake light will come on.

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The brake liquid never goes that low even with severe pad wear.

It does unless someone keeps the reservoir topped off.

Keith is absolutely right.
The system is designed not only to let you know the fluid is low, but also to let you know when the pads are. The volume of fluid that when displaced allows the float to trigger the warning light is equivalent to the volume of fluid that transfers to the calipers to fill the chambers when the pads become low. As a matter of fact it could be argued that the latter purpose, pad wear, is really the primary purpose is really the primary purpose of the warning system. .

@COROLLAGUY1 , easy enough to decide the issue of what fluid level triggers the warning light. Use a suction device to lower the brake fluid. At some point the low brake fluid light will pop on. That’s the level. On my own Corolla it comes on just a little below the “low” level marked on the plastic bottle. I wonder how that sensor works? Optical or thermal probably.

Whenever I wanted to check the master cylinder fluid level sensor to see if it was triggering the BRAKE light I just unplugged and plugged it repeatedly. If the light went on and off the mystery was solved. Likewise the E-brake switch.

My guess would be electromechanically. A simple on/off switch with a float attached.

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It’s was the brake fluid being low, thanks for all the suggestions.

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For the future, let’s not complicate the issue. Usually it is brake fluid low but could be the parking brake still on. The fluid sensor is just a simple one like the radiator level, washer fluid, etc. I have had a bad one though that required replacing the master, but that was one out of umpteen cars and over a million miles.

Glad the problem was dimple.

If the fluid was low enough to trip the sensor be sure to get your brakes checked.

That may well be true, but you apparently own(ed) a 1999 Toyota, and the the OP posted a question in regard to a 1999 Buick LeSable.
It is entirely possible that GM’s technology functioned differently from the technology of Toyota’s vehicles in 1999.

:thinking:

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