Hey man/girl, ask a macanic. Mabie that will help u.
Check your brake fluid. You may need to replace a speed sensor on one of the brake assemblies.
Check to see if Brake lamps work when brake pedal is pressed. If not gear shifter is locked for safety so replace fuse or repair brake lamp switch.
Look at the uper end of the brake pedal under the dash area
Probably cause by a worn out/defective brake light switch.
Check out this post: http://www.mavromatic.com/2007/03/diy-part-i-replacing-rear-rotors-and-brake-pads-on-a-land-rover-discovery-ii/
it is under the hood right in the corner nearest the drivers door and it takes DOT 4 Brake fluid
To change the brake master cylinder on a 1999 Land Rover Discovery, first, ensure the vehicle is on a flat surface and the engine is off. Disconnect the negative battery terminal, then remove the brake fluid reservoir cap and siphon out the fluid. Disconnect the brake lines from the master cylinder, unbolt the cylinder from the brake booster, and replace it with the new unit. Reconnect the brake lines, refill the reservoir with brake fluid, and bleed the brake system to remove any air.
Carefully pry pad wear sensor from brake pad. Then insert brake pad wear sensor into cutout in new pad where applicable.
Hub seal is leaking
the brake fluid level is low in your master cylinder, add some brake fluid and the light will stay off
To replace the brake pads on a Rover 75, first, safely lift the vehicle and remove the wheel. Next, use a brake caliper tool to compress the caliper piston, then unbolt the caliper and remove it from the rotor. Take out the old brake pads and replace them with new ones, ensuring they are properly aligned. Finally, reattach the caliper, replace the wheel, and lower the vehicle before testing the brakes.