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Brake Warning Light On, then Off

The first time the brake warning light came on, I stopped the car (gratefully so) and checked the fluid. It’s pretty clear, and in the middle between Min & Max.



Oh, this is a 1995 Toyota T100 base model - manual tranny, 2WD, long 8’ bed, 4 cylinder engine. It’s grey, if that matters.



Actually, the first thing I did was to jimmy the handbrake a bit. Did not make any difference.



Then, the light went off. And I’ve been driving it since.



This fall, the light comes on when accelerating at times, and stays on a bit, then goes off either during deceleration or just on its own.



Should I worry?

How worn or old are your brake pads? Sometimes really worn brakes will have this appear.

Add a little brake fluid to be sure,

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How old is the brake fluid. If more than three years, now would be a good time to change it. Is that brake light, a brake fluid warning or is it a bake warning light. Check your owner’s manual. It may be time for a brake job.

Note, I only mentioned changing the brake fluid because as long as you are looking at them, now would be a good time to change the fluid if due.

It’s the red warning light for the brakes.

If the fluid level is truly okay, then your possibilities are:
Failing brake fluid level (float) sensor.
Failing parking brake applied switch.
Wiring that is shorting somewhere.
And apparently (oddly enough) some alternator failures can trigger this light.

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Fill it up to max and it’ll go away, but be aware that brake fluid doesn’t just disappear-- the reason why the level is low is that the hydraulic system has gotten larger as the friction material has worn down. In other words, you need brakes or are going to need them very soon.

Here’s a STRONG indication: the light only comes on during driving WHEN ACCELERATING. Not every time, more often when the car is not fully warmed up.

Yes, it’s the fluid sloshing around in the fluid reservoir. As the brakes warm up, the parts and fluid expand ever so slightly, making it slosh below the sensor somewhat less often.

Just top off the fluid and the light will go away, but be prepared to do a brake job soon.

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Ok, I’ve topped up the fluid. It was firmly in the middle between Min and Max, and now it’s a bit under Max. On three short drives today, the brake light did not come on.

Will check back in a week or two to update this.

Ok, Thanksgiving is less than a week away, and I am thankful that my brake warning light has not come on once since topping off the fluid.

Thanks to GreasyJack!

I’m experiencing the same issue. The Brake light was on and I just changed the brakes and rotors. After I finished it went out momentarily then came back on. Brake fluid is full and new brakes and rotors. What else could it be?

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