Chevrolet New Sail (2010). Manual — part 24

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4. Displacement Pump
5. Power Accumulator
6. Intake Valve
7. Right Rear Brake Caliper
8. Outlet Valve
9. Outlet Valve
10. Left Front Brake Caliper
11. Intake Valve

15. Outlet Valve
16. Outlet Valve
17. Left Rear Brake Caliper
18. Non-Return Valve
19. Intake Valve
20. Power Accumulator
21. Displacement Pump
22. Damper
23. Orifice

5.3.2 Anti-Lock Braking Mode - Connection

If, in pressure maintaining or pressure drop mode, the electronic brake control module detects that the wheel

slip rate has been reduced, then the electronic brake control module will increase the brake fluid pressure of the
corresponding wheel through applying the Master Cylinder pressure. At this point, the intake valve is open and the
outlet valve is closed so that the pressure of the normal brake Master Cylinder can be applied to the wheels.

1. Master Cylinder
2. Orifice
3. Damper

13. Intake Valve
14. Right Front Brake Caliper
15. Outlet Valve

95

Chevrolet 2010 New Sail New Technical Training

- Learner's Manual

4. Displacement Pump
5. Power Accumulator
6. Intake Valve
7. Right Rear Brake Caliper
8. Outlet Valve
9. Outlet Valve
10. Left Front Brake Caliper
11. Intake Valve
12. Motor

16. Outlet Valve
17. Left Rear Brake Caliper
18. Non-Return Valve
19. Intake Valve
20. Power Accumulator
21. Displacement Pump
22. Damper
23. Orifice

5.3.3 Anti-Lock Braking Mode - Maintenance

When the electronic brake control module detects wheel slip, it will close the intake valve and maintain the

outlet valve in the brake pressure regulator valve as closed to isolate the system. In this way, the stability of the oil
pressure in the brakes can be maintained so that there is no oil pressure rise and drop.

1. Master Cylinder
2. Orifice
3. Damper

13. Intake Valve
14. Right Front Brake Caliper
15. Outlet Valve

96

4. Displacement Pump
5. Power Accumulator
6. Intake Valve
7. Right Rear Brake Caliper
8. Outlet Valve
9. Outlet Valve
10. Left Front Brake Caliper
11. Intake Valve
12. Motor

16. Outlet Valve
17. Left Rear Brake Caliper
18. Non-Return Valve
19. Intake Valve
20. Power Accumulator
21. Displacement Pump
22. Damper
23. Orifice

5.3.4 Anti-Lock Braking Mode - Separation

If the electronic brake control module still detects wheel slip in the pressure maintaining mode, then the

electronic brake control module will decline the brake fluid pressure of the corresponding wheel. The intake valve
remains closed and the outlet valve is open. Redundant oil and pressure are temporarily stored in the power
accumulator inside the brake pressure regulator valve until the oil pump is able to return oil to the fluid storage
tank of the Master Cylinder.

1. Master Cylinder
2. Orifice
3. Damper

12. Motor
13. Intake Valve
14. Right Front Brake Caliper

97

Chevrolet 2010 New Sail New Technical Training

- Learner's Manual

4. Displacement Pump
5. Power Accumulator
6. Intake Valve
7. Right Rear Brake Caliper
8. Outlet Valve
9. Outlet Valve
10. Left Front Brake Caliper
11. Intake Valve

15. Outlet Valve
16. Outlet Valve
17. Left Rear Brake Caliper
18. Non-Return Valve
19. Intake Valve
20. Power Accumulator
21. Displacement Pump
22. Damper
23. Orifice

5.4 Decoupled Dynamic Rear Proportioning

（DDRP）

The DDRP

（decoupled dynamic rear proportioning）system is a proportioning system, which is used for

maintaining vehicle stability during braking. Under normal braking conditions, the braking force of the rear
wheels is on the small side because the vehicle’s center of gravity moves forward. DDRP maintains the brake
pressure required by the rear wheels through the rear intake and outlet valves of the anti-lock braking system

（ABS）to provide effective braking effect and vehicle stability. In the DDRP system, the power of the rear

maintaining solenoid valve is supplied by the ignition circuit.

If one of the following malfunctions occurs, the red brake warning light will be illuminated.

z The two wheel speed sensors on the same axle are out of service.

z The rear intake solenoid valve is out of service.

z The accumulator 2 and the motor input are short-circuited against the ground.

z The accumulator 1 and the electronic brake control module are open-circuited or short-circuited against

the ground.

z The motor ground circuit is open-circuited or short-circuited against the accumulator.

z The ground circuit of the electronic brake control module is open-circuited or short-circuited against the

accumulator.

z The ignition circuit is open-circuited or short-circuited against the ground.