Geely EC715 2009, Workshop Manual

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Pressure Maintaining
When the wheel spins, ABS control module closes the inlet
valve and keeps the valve closed and isolated from the system.
It maintains the braking fluid pressure without increasing or
decreasing.
Pressure Decrease
When the wheel spins, ABS control module reduces the
pressure to individual wheels during deceleration. The inlet
valve is closed, while the outlet valve is open. The excess fluid
is stored in the accumulator until the ABS pump returns the fluid
to the master cylinder.
Pressure Increase
When the wheel does not spin, ABS control module gradually
increases the braking pressure to each wheel to reduce wheel
speed. The inlet valve is open, while the outlet valve is closed.
The increased pressure is provided by the brake master
cylinder.
Electronic Brake Force Distribution (EBD)
Each wheel attached ground conditions may be different, then
the ground friction coefficient will be different. During braking,
the vehicle gravity center will change, so the vehicle is prone
to skid when braking, tilt and roll and so forth. EBD's function
is to calculate four tires friction difference as a result of different
adhesion coefficients at the braking moment, then adjust the
hydraulic unit electromagnetic valve. The valve adjusts as the
preset program to match the system power to the friction
(adhesion), ensure vehicle braking smooth and safety. Under
the emergency braking situation, before the ABS action EBD
has balanced each wheel grip, to prevent tail-flick and the
lateral movement. EBD is actually an additional ABS function.
Based on road and load changes, it automatically adjusts the
braking force distribution, improves and the ABS efficiency.
6-72 ABS / TCS / EBD / ESP Brake System
EC718/EC718RV EC715/EC715RV 10/2009