releasing parking brake, parking brakes, hydraulic brakes

why doesnt parking brake release?  show diagram please. thank you

Answer
    Well, that's a pretty vague question.  If I knew what car I might be able to help.  Most parking brakes have a lever, either on the console or under the dash, that you move to activate the brake.  The lever pulls a cable which pulls the lever at the other end and activates the parking brake.  The parking brake is purely mechanical.  Even if it uses the pads/shoes used by the regular hydraulic brakes, it doesn't use any of the other parts to activate them.  The reason most parking brakes get stuck is that the cable becomes stretched.  Then, when you activate it, the extra length allows it to slip out of the groove that it rides in.  When it slips out, it gets wedged in place and won't release.  You have to find where along the length of the cable the jam is, and pry it out with a screwdriver or some such.  Just start at the brake handle (or pedal) and follow the cable back to the wheel.  You'll need a flashlight for under the dash and under the car.  Every car is different, but they all work on the same principle.  If the cable came out of the groove it is stretched and should be replaced before it happens again.
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