ABS with EBD Operation

Based on the signals received from the 4 wheel speed sensors, the skid control ECU calculates each wheel speed and deceleration, and checks wheel slipping conditions. And according to the slipping condition, the skid control ECU controls the pressure holding valve and pressure reduction valve in order to adjust the fluid pressure of the each wheel cylinder in the following 3 modes: pressure reduction, pressure holding, and pressure increase modes.

Not Activated

Normal Braking


Increase Mode

Holding Mode

Reduction Mode

Hydraulic Circuit

Port A

Pressure Holding Valve ri

Port B

Pressure T .

Reduction Valve T° W Cylinder

Reservoir and Pump

From Wheel Cylinder

Pressure Holding Valve (Port A)

OFF (Open)

ON (Close)

Pressure Reduction Valve (Port B)

OFF (Close)

Wheel Cylinder Pressure







Was this article helpful?

0 0
Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

Don't pay hundreds of dollars to find out what is wrong with your car. This book is dedicated to helping the do it yourself home and independent technician understand and use OBD-II technology to diagnose and repair their own vehicles.

Get My Free Ebook

Post a comment