There are two Kia disc brake calipers that are critically responsible for stopping your vehicle. This is the place where the hydraulic pressure is applied, forcing the pads against the brake rotors which brings your Kia to a stop. The only moving part in the disc brake caliper is the piston in its interior. As the brake pads wear, the piston moves outwards. Around the piston of the Kia disc brake caliper is a polymer seal. It is this seal that will wear out over time requiring the caliper's replacement or refurbishment. When this occurs, the brake fluid will leak out causing the brake pedal to feel soft. It is possible to rebuild the disc brake caliper, but you must have the necessary tools and equipment. To save time and some frustration on this procedure the Kia owner can purchase a new or already rebuilt disc brake caliper. What must be remembered is that the new disc brake caliper will have air trapped inside of it that must be removed for it to be able to function as it was designed too. This procedure is called bleeding the brakes. Once the new caliper is in place on the rotor pressure can be applied to the brake system by the brake pedal being depressed. This pressure cannot be released even when the pedal reaches the floor. With pressure on the system, the nipple on the top of the caliper is opened allowing for the air to escape. Once the nipple is closed, the pressure on the brake pedal can be released. This process will have to be repeated until only brake fluid is coming out of the nipple when it is opened. At that point your Kia is read to be driven safely on the road.