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BRAKES
9
6. BRAKE HYDRAULIC LINES
SCHEMATIC CIRCUIT DIAGRAM OF ABS BRAKE LINE
General:
Vehicle braking is provided by Disc Brakes on the
front wheels and Drum Brakes on the rear wheels.
Under normal brake operation, brake pedal
movement is assisted by the Booster assembly
and transmitted to the Tandem Master Cylinder
(TMC) assembly. The TMC assembly converts
brake pedal movement to hydraulic pressure.
Vacuum for the brake servo assembly is obtained
from the engine inlet manifold (for petrol engines)
or a vacuum pump (for diesel models), through a
vacuum line and non-return valve.
Anti-lock braking system consists of a Hydraulic
modulator with integrated Electronic control unit,
four-wheel speed sensors (one located at each
wheel) and 2 warning lamps in the instrument
cluster (1(yellow for ABS and 1(Red) for EBD).
The brake pipes are connected to the brakes
through the ABS ECU / HCU. They make two
independent circuits diagonally split. The primary
circuit connects the Front Right and the Rear Left
brake while the secondary connects Front Left
and Rear Right brake through ABS unit. Internal
to the Hydraulic modulator each brake has a pair
of solenoid valves, one inlet and one outlet; these
are activated by the ECU to control the brake
force on individual wheels whenever required.