1998 Toyota Sienna brakes system doesn't work

1998 TOYOTA SIENNA
179,000 MILES • AUTOMATIC
Avatar
KHENDRIXX
  • MEMBER
  • 1 POST
What would cause the vans brake to not work at all. The pedal easily just goes straight to the floor..no pressure at all..no slowing down and no stop.
Sep 18, 2014 at 10:39 PM
Advertisement
Avatar
CARADIODOC
  • ASE Certified Mechanic
  • 34,321 POSTS
  • ASE Certified Mechanic
There's a number of possibilities. If the pedal swings freely, something has become disconnected under the dash. Ford had a big problem with that some years ago, but otherwise that is very uncommon. Brake pedals are designed with preventing that in mind.

More commonly there's a leak in one of the hydraulic circuits. There is always a second system that should give you some brakes. It won't be much, but it's extremely rare to lose all of the brakes. The first thing is to check the brake fluid level. When checking, and especially when adding, be absolutely certain to not get the slightest hint of petroleum product like engine oil, transmission fluid, or power steering fluid in there. Doing so will create a REAL expensive repair bill.

If the fluid is empty, there's a leak somewhere and it shouldn't be too hard to identify where. If the level is real low but not empty, suspect the front brake pads are in need of replacement. If they were grinding metal-on-metal and ignored for a while, a piston can fall out of the brake caliper leading to loss of brake fluid.

Never fill the master cylinder reservoir unless a brake job was just completed. To replace the front pads, the pistons have to be pushed back into the calipers to make room for them. Doing that pushes a lot of brake fluid back up to the reservoir where it will overflow and make a mess if someone filled it previously.

To provide a better suggestion of the cause of the problem, you have to provide some details or history of anything you observed that led up to this.
Sep 18, 2014 at 11:09 PM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.