Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Principles of Operation

Principles of Operation
Applying the brake pedal uses lever action to push a rod into the brake booster, which through the use of vacuum, boost the force of the rod and then transmits this force into the master cylinder. This produces hydraulic pressure in the master cylinder. The hydraulic pressure is transmitted by brake fluid through the brake lines to the individual brake calipers or wheel cylinders. The brake calipers or wheel cylinders use hydraulic pressure to apply the pads or shoes. The application of the brake pads or shoes will cause the rotation of the wheels to slow or stop depending on how much brake pressure is applied. The parking brakes carry out the same function except that they are mechanically actuated by a cable that connects only to the rear brakes.