Pressing brake pedal a lot and ABS light alarm

[shogun2fire]

I replaced my rear brakes just now. I turned the car on and then pressed the brake pedal many times really quickly (10-15) and then the ABS warning light would go on and the alarm sounds. If I do not press the brake pedal for a couple seconds the alarm goes off. The manual says this is normal and I'm wondering if this is anything to be worried about. The fluid level while the car is idling is between the MAX and MIN lines.

 

[APKhaos]

Assuming you replaced pads, the pistons would have been fully compressed.
First thing to do after ANY brake job is to make sure you pump the pistons out so that the pads contact the rotors. If you forget to do this [we all have at some time] you'll have a scary 'no brakes' moment until the pistons are pumped out.

If you have a firm high pedal now, you should be OK.
If you don't have a firm hard pedal, check your work carefully. Look for fluid leaks around each caliper. Check fluid levels etc.
If you have have a firm high pedal AND the ABS light is setting, check your abs sensor leads especially around the axles you were working on. Its easy to have damaged the sensor lead without noticing, and that will give you ABS lights every time.

 

[shogun2fire]

Brake pad is firm after I turned the car on and pressed the pedal several times. The alarm would come on after I pressed the pedal many times very quickly so I turned the car off.

Let the car sit for a minute and then turned it back on and there's no ABS light or alarm (abs light comes on for a second when I turn the key on but that's normal). Drove the car around for 15 minutes and everything seemed normal. No moments of having no brakes and no squeaks or rattling.

The abs light would just go on if I press the brake pedal a lot in very short intervals, which would never happen in real driving as nobody presses the brake pedal that fast that many times. Just wondering if that is to be expected.

 

[APKhaos]

Toyota ABS controller uses multiple rapid brake pedal presses as a control function. Reading and clearing ABS codes uses this method. Your multiple rapid presses are probably spooking the controller.

If you have a good pedal and normal brake ops AND no ABS light while driving then all is OK.

 

[uHu]

Depressing the pedal several times quickly makes the booster pressure go down. When it goes under a certain pressure, the alarm goes off. This is normal behaviour.
Btw, the fluid level is to be checked when the booster accumulator is emptied, i.e. not when it's idling or ign on.

 

[APKhaos]

Depressing the pedal several times quickly makes the booster pressure go down. When it goes under a certain pressure, the alarm goes off. This is normal behaviour.

Good point. Didn't know that. Thanks!