Brake pedal has no pressure, goes to the floor

astrob0y

Member
:
08 Mazda 3
My brake pedal has no pressure and when pressed it goes to the floor. This morning the brake light was on and I didn't get a chance to check he brake fluid, I was in a rush so I drove the car with the light on and the rake pedal had very little pressure, very spongy and when pressed hard it goes to the floor. I brought it into the garage, checked the level and it was low, way below the min line. I filled the reservoir and the brake light on the dash cleared but there is no pressure on the brake pedal now... Bad master cylinder? Or should I try bleeding the brakes?
 
check to make sure you have brake pad left, too. if the pads wear down too far, it saps fluid from the resovoir. if the fluid in the resovoir gets too low, the brake light comes on. if the fluid gets WAY too low, the pdeal wont have anything to push and will travel to the floor.

so, check the pads... if the pads are good, check for leaks... if no leaks, top up the fluid, bleed the lines, and hope the fluid sticks around.
 
check to make sure you have brake pad left, too. if the pads wear down too far, it saps fluid from the resovoir. if the fluid in the resovoir gets too low, the brake light comes on. if the fluid gets WAY too low, the pdeal wont have anything to push and will travel to the floor.

so, check the pads... if the pads are good, check for leaks... if no leaks, top up the fluid, bleed the lines, and hope the fluid sticks around.

You should never just top off the fluid! if its low its due to A) a leak, or B) worn out brake pads

Edit: If its due to low brake pads the fluid will be pressed back up when you press the pistons in for the new pads.
 
You should never just top off the fluid! if its low its due to A) a leak, or B) worn out brake pads

Edit: If its due to low brake pads the fluid will be pressed back up when you press the pistons in for the new pads.

thats why i put my check list in the order that i did.
 
I changed the pads about 20k miles ago (at 60k miles), so the pads should be good, I'll check the lines to see if there's any leak when I get home. Thanks for the replies!
 
Don't think there's a leak, the level doesn't drop when i keep pressing the pedal. I guess it's time to bleed the brakes. If that doesn't work then it's a bad master cylinder?..
 
Back