my BMW 5 Series F10/F11 (2010-2017) brake pedal goes to the floor how to fix it

Solution

1. Preparation

• Gather tools and parts.
• Ensure the vehicle is on a level surface and secure it with wheel chocks.
• Disconnect the battery for safety.

2. Inspect and Repair Leaks

• Tools Required: Wrench set, brake line repair kit, or replacement lines.
• Check all brake lines and connections for leaks.
• If leaks are found, replace damaged lines or fittings:
  • Remove the affected line using a wrench.
  • Install the new line and tighten it to the manufacturer's specified torque.

3. Bleed the Brake System

• Tools Required: Brake bleeder kit, clear tubing, container for old fluid.
• Open the bleeder valve on the farthest brake caliper from the master cylinder.
• Attach the clear tubing to the valve and place the other end in the container.
• Have an assistant press the brake pedal slowly while you open the valve slightly to release air and fluid.
• Repeat this process for each brake caliper in the order closest to the master cylinder.
• Ensure the brake fluid reservoir is kept topped up during bleeding.

4. Replace the Master Cylinder (if necessary)

• Tools Required: Socket set, line wrench, brake fluid.
• Disconnect the brake lines from the master cylinder using a line wrench.
• Remove the master cylinder mounting bolts and carefully take it off.
• Install the new master cylinder:
  • Align and secure the new master cylinder with mounting bolts to the manufacturer's torque specifications.
  • Reconnect the brake lines and ensure they are tightened properly.