Mazda 3 Dynamic Stability Control DSC HU/CM

Using a compact and lightweight ruggedized DSC HU/CM integrated unit

The DSC HU/CM calculates the input signals from all sensors and controls the solenoid valve and the pump motor (on/off), regulates the pressure of the working fluid in the brake cylinders and activates the functions of the dynamic stability system (ABS, electronic brake force distribution (EBD) ), TCS, DSC and Brake Assist)

The design and operation of the DSC hydraulic unit is similar to that of the modern 323 (BJ) hydraulic unit, with the exception of the emergency brake booster.

The DSC HU/CM outputs the engine torque control signal and the vehicle speed signal via CAN.

The DSC HU/CM also outputs the vehicle speed signal by wire

Fig. Fig. 1. Scheme of operation of the combined dynamic stability control sensor of the Mazda 3 car: 1 – appearance; 2 - the front of the car; 3 – output voltage; 4 - acceleration; 5 - left turn; 6 - longitudinal acceleration; 7 - right turn; 8 - output voltage; 9 - left turn; 10 – yaw rate; 11 - right turn

Purpose and functions of the DSC system


Calculates the input signal from each sensor, and controls the brake fluid pressure in the brake system of each wheel, activates each function of the DSC system (anti-lock brakes, EBD, TCS, and DSC)

Outputs a control signal that regulates the function of the TCS/DSC system and the speed signal via CAN

Outputs speed signal to audio unit, wiper and washer switch, car-navigation unit, cruise control actuator and wire alignment control unit

Controls the diagnostic system and the reliability system when faults are detected in the DSC system

PCM block

Controls motor torque based on signal from DSC HU/CM

Transmits engine status and wheel information to DSC HU/CM via CAN

DSC warning light

Notifies the driver that the DSC system is operating (vehicle is in side slip)

Notifies the driver of TCS (Drive Wheel Slip Situation)

DSC switch

Disabling the system at the request of the driver is transmitted to the DSC HU/CM

DSC shutdown warning light

Notifies the driver that the DSC DSC system has been deactivated

Notifies the driver that the DSC system has been disabled by Reliability Management

Wheel speed sensor

Detects the rotation status of each wheel and sends a signal to the DSC HU/CM

Combined sensor

Detects the lateral g-force and the yaw rate (corner rate) of the vehicle and transmits this information to the DSC HU/CM

Rotation angle sensor

Determines the angle of rotation and sends this information to the DSC HU/CM

DSC warning light operation


DSC warning light

TCS,DCS not working


TCS works

Blinking (at 0.5s intervals)

DSC works

Blinking (at 0.5s intervals)

DSC HU/CM Dynamic Stability Unit Functions

ABS control

When braking, it maintains the stability of the direction of movement, increases the reliability of control and ensures a shorter braking distance by controlling the pressure of the brake fluid

EBD (Electronic Brakeforce Distribution) control

Prevents rear wheel lockup by optimally distributing brake fluid pressure between the front and rear brakes according to vehicle load, road surface conditions and vehicle speed

TCS Management

Provides no Danger when starting off and accelerating by maintaining tractive effort within the limits allowed by the coefficient of adhesion, in accordance with road conditions and vehicle speed

DSC system control

Prevents vehicle oversteer or understeer by controlling engine torque and braking force at each wheel to ensure vehicle stability

Brake assist control

Controls the pressure of the working fluid in the caliper cylinders during emergency braking, provides increased fluid pressure in the cylinder of each wheel

Vehicle speed output

The result of the calculation from the signals of 4 wheel speed sensors is output as a speed signal to the CAN line, to the wiper and washer switch, cruise control system actuator, audio unit and wire alignment control unit