Brake Hose Given that both your brake hose and pipe play a vital role in helping your brakes to function, it's only right that your vehicle won't pass its MOT if they are worn out. The brake hose carries hydraulic fluid from the brake pipe to the callipers, forcing the callipers together and clamping the brake pads around the rotors when you place your foot on the brake pedal. The brake pipe is a rigid (usually steel – which can corrode over time) pipe that transfers pressurised brake fluid from the master cylinder, where brake fluid is stored, to the brake hoses. The brake hose is made of flexible, reinforced rubber piping that is designed to withstand oil and water as well as the high pressure exerted when the braking system is in use; however, being constantly exposed to the elements and in regular movement, it will, eventually, wear out. It’s essential to replace a worn hose or braking will be affected; this safety issue would result in a failed MOT. Brake failure is certainly not worth the risk. Make sure you check the integrity of your braking system regularly.