Description & Operation: Plunger

The plunger consists of a center valve, plunger piston and gradient switch. The plunger piston separates the primary chamber (brake fluid passage from master cylinder, via ABS actuator, to rear brake) and the secondary chamber (oil passage from pressure solenoid valve). Under normal braking, TCS not operating, brake fluid pressure travels through the primary chamber to rear brake. With the TCS operating, oil pressure from pressure solenoid valve is applied to plunger piston through gradient switch. The center valve closes the primary chamber. Brake operating fluid pressure is produced by the plunger piston moving to the left. See Figure .