Toyota 47025-60012 Brake Master Cylinder Sub-Assembly

Removal steps 1. Park on a level surface, chock wheels, wear eye protection and gloves, and relieve any residual system pressure by pumping the brake pedal several times with the engine off. 2. Open the hood, clean the area around the brake fluid reservoir to prevent contamination, and protect painted surfaces from spills. 3. Disconnect the negative battery cable to disable electrical circuits before touching any sensors or connectors. 4. Siphon or absorb excess brake fluid from the reservoir to reduce spillage during removal and keep the reservoir cap loosely in place. 5. Label or mark brake lines and electrical connectors so they can be reinstalled correctly, then disconnect electrical plugs for level or pressure sensors. 6. Using an appropriate line wrench, loosen and remove the brake fluid lines from the master cylinder while catching fluid in a clean container and immediately plugging or capping line fittings to limit air entry and contamination. 7. Remove the fasteners that secure the master cylinder to the booster or firewall (fastener type and location vary by design) and carefully pull the assembly straight out to avoid bending lines or damaging the booster. 8. Set the removed master cylinder upright to prevent further spillage and dispose of or store drained fluid in accordance with local regulations. Installation steps 1. Bench-bleed the replacement master cylinder before installation following the component manufacturer's bench-bleeding method (typically tubing from ports back into the reservoir while slowly pressing the piston until bubbles stop). 2. Position the new master cylinder onto the booster or mounting flange, align it, and install the mounting fasteners, tightening them evenly (consult a shop manual for specified torque). 3. Reinstall the brake lines with a proper flare-nut/line wrench, remove any plugs, and snug fittings until leak-free; do not overtighten without torque spec. 4. Reconnect electrical connectors for sensors and ensure wiring is routed away from hot or moving parts. 5. Refill the reservoir with the correct type of fresh brake fluid and keep the cap loosely installed during bleeding. 6. Bleed the brake system to remove air-commonly starting at the wheel farthest from the master cylinder-using a helper or pressure/vacuum bleeder until the pedal feels firm and no air is present; monitor the fluid level so it never runs dry. 7. Inspect all fittings, mounting points, and lines for leaks while applying steady pedal pressure. 8. Reconnect the negative battery cable, start the engine, and verify proper brake booster assist and that warning lights behave normally. 9. Perform a low-speed functional test in a safe area to confirm pedal firmness and braking performance, then recheck for leaks and fluid level. 10. Clean any spilled fluid from vehicle surfaces and dispose of used brake fluid and contaminated rags properly. Repair tip: Use a dedicated bench-bleed kit or short clear tubing and a block to prevent trapped air; always keep the reservoir topped up during bleeding to avoid introducing new air.