Soft brake/ABS

Hi and thanks for using 2CarPros.com.

If the brake pedal went to the floor, the master cylinder is still full, and there are no leaks, the master cylinder is bad. There are pistons in the master cylinder which are to create pressure when you apply the brakes. If it goes to the floor, they are bypassing the brake fluid.

I have attached a picture for you to see the internal components of the master cylinder. Numbers 10 and 11 are the pistons I am referring to. Please keep in mind, this system is designed to have two separate systems. You have a primary and secondary. It would be very odd for both to fail. However, it is designed so the primary actuates the front brakes and the secondary operates the rear. If one fails, you will still have the other to help stop. Regardless, the brake pedal will go to the floor.

Take a look at the picture to better understand. Also, I feel this is the problem based on the idea there are no leaks, the fluid is still full.

Additionally, here are a few links to help better explain your symptoms and if you chose to do the repair yourself, there are general directions:

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

https://www.2carpros.com/articles/how-to-replace-a-brake-master-cylinder

Let me know if this helps. If you have other questions, let me know. If you decide to do it yourself, I am here to help.

Take care,
Joe