How To Bleeding ABS Brake System Correctly For Your Car

Why & When Need To Bleeding ABS System?

An anti-skid braking system or anti-lock braking system(also short called ABS),it is a hydraulic brake system,the actions of brake system is performed power by hydraulic pressure.The compressive property of brake fluid is excellent,its volume will not be reduced when inflicted strong pressure.Compare to the brake fluid,the air in the brake system have poor compressive property,The volume of air will reduce when it suffering strong pressure.If brake fluid in the brake system is mixed with air,the brake pressure provided by booster pump will work to reduce volum of air when braking,instead of providing the brake pressure directly.So it will make brake system insensitive and expose us under the risk.

 

There will be a need to replace an ABS modulator or other hydraulic component, such as a pump/motor or even a master cylinder, on some systems.And if your car perform above operations,it most likely that the brake fluid in the brake system is mixed with the air,then you need to bleeding ABS system to enhance brake system performance.

Bleeding ABS Brake System Principle:

The oil circuit of brake system is a closed loop,the method of bleeding air is circulation of loop.Generally,the filling valve of brake system is setted to current path and delivery valve is open circuit,so we just consider the delivery valve.Only active delivery valve to make oil circuit circle circulated.At the same time,press the brake pedal to enhance oil pressure to promote the brake fluid circulate in the loop.

 

Bleeding ABS System by Special device or Manually?

Usually,a lot of people bleeding ABS by manually,but if you wanna a better effect of bleeding ABS,it is recommand to bleeding ABS by special device.Only air of filling cicuit and brake sub pump can be discharge by manual bleeding,it can not bleeding the air in the delivery valve. All air in the system can be discharged by special device.

 

How To Bleeding ABS Brake System?

According to the ABS type,the method of bleeding ABS are different:

For BOSCH ABS System:

Order:

Left rear wheel–>Left front wheel–>Right front wheel–>Right rear wheel

 

1. Before bleeding ABS,you need to open bleeding bolt of left rear wheel.

2. Press brake pedal during bleeding ABS.

3. You will sound the sound of delivery valve actived.

4. When the bleeding complete,the device will remind you to close left rear bleeding bolt and open the left front wheel bleeding bolt.

5. It will remind you to close left front wheel bleed bolt and open bleeding bolt of right front.

6. When the bleeding of right front wheel,the device will active the pump and right front wheel delivery valve.So you will sound the sound of pump.The bleeding of right front wheel and right rear wheel will take more time than left side wheel.

7 When 4 wheel ABS bleeding complete,the device will remind you bleeding ABS completely.

 

For other ABS System:

Order:

Right rear wheel–>left rear wheel–>left front wheel–>right front wheel

1. Before bleeding ABS,you need to open bleeding bolt of left rear wheel.

2. Press brake pedal during bleeding ABS.

3. When starting bleeding,the device will active pump and delivery valve,you would sound the sound from pump and delivery valve.

4. The pump will work on all the time during bleeding,and delivery valve will open and close alternately.

5. There will be a pause of pump when one of wheel bleeding completely,then the device show closed right rear wheel bolt and open left rear wheel blot,select start to begin bleeding of left rear wheel.

6. Follow the gudie of device to complete bleeding of each wheel.

 

Here is a real case Bleeding ABS operation,click to read detail:

VW Tiguan Bleeding ABS Brake Pump By X431