How to Replace Brake Pads on BMW 525 with Electronic System

This guide shows how to replace the brake pads on your car. The first step is to release the parking brake using the internal lever. Next, disconnect the control cable of the actuator at the brake housing. To do this, press on the safety plug and, using a small screwdriver to lift the plug, pull out the connector. Now, using a hex wrench and a special tool, remove the two guide bolts of the brake caliper and then pull the piston and actuator out of the housing (using a lever for assistance). Next, remove the two Torx screws that secure the actuator to the brake piston and then remove the electronic control. Using a Torx screwdriver, turn clockwise (as far as it will go) to retract the parking brake assembly. Now, using a piston compression tool, retract the piston and then you can reinstall the parking brake actuator. At this point, you can remove the old brake pads and proceed to replace the rotor. You need to detach the caliper support by unscrewing the mounting bolts. Using an Allen bit, unscrew the retaining bolt of the rotor, and if there is rust on the hub, use a hammer to help remove the rotor. Clean the hub with appropriate cleaner and, after drying it well, apply some anti-seize compound. Taking care not to contaminate the faces of the rotor with grease, install the new rotor aligning the Allen pin holes and clean the rotor again of any grease deposits. Clean the caliper housing and apply grease to the friction areas between the pads and the housing. Finally, reassemble this last piece using the mounting bolts. Install the new pads and reinstall the brake piston. After tightening according to the specifications in the manual, reactivate the parking brake. The operation is now complete. The tools required for the procedure are:
- Hex wrench for unscrewing various bolts;
- Special 15 mm wrench for unscrewing actuator bolts;
- Mechanic's lever;
- Torx screwdriver;
- Piston compressor;
- Allen bit for removing the brake rotor;
- Hammer.