Epb Construction And Operation - Subaru Legacy 2015 Technicians Reference Booklet

2015 Legacy and Outback
New Technology Training
(Module 926)

EPB Construction and Operation

8-12
Caliper (Artwork)
The EPB operates from the movement of a brushed DC voltage motor which is controlled by the
Hydraulic Control Unit. A series of worm gears and reduction gears provide bidirectional movement
of a ball nut that is keyed to the hydraulic piston. If the EPB is activated, the ball nut is screwed
downward into the back face of the hydraulic piston and the piston moves into the inner brake pad.
The pushing force pulls the caliper inward which pulls the outer brake pad into the rotor. When
the EPB is released, the ball nut is reversed and the square cut caliper seal pulls the piston away
from the inner brake pad and releases tension to the caliper and the outer brake pad.
June 2014
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